ZERO EDGE (NEGATIVE EDGE) SKIMMER VS INTAKE BAY SKIMMER

In this video, John Adams of Modern Design Aquascaping Inc., TEACHES the viewers about two Advanced Skimming Systems. The Negative Edge system, also known as a zero edge, is compared to an Intake Bay skimming system. John covers the differences of each as well as the similarities to help a prospective pond owner understand both and decide if one of these skimming systems might be right for them! The video does not cover how to design these, simply how they work. Please ask questions in the comments if you have any!
Modern Design Aquascaping has been building custom water features since 2000 and has been a Certified Aquascape Contractor since 2002. They have built in 5 countries, and over a dozen states in the U.S. You may reach them in East Tennessee at:
PHONE-[phone]
WEB-www.MDAquascaping.com
FaceBook: Modern Design Aquascaping
KZbin: / moderndesignaquascapin...
The KZbin channel is geared towards education on proper construction methods for water features and highlights many cool projects that the Modern Design Aquascaping team gets to be a part of!
Happy Pondering ;)

[@joshuagellner7176]

Thanks for posting these videos. They are very inspiring and very helpful. I'm working on designing a garden/wildlife pond and I'm interested in using an intake bay instead of a skimmer. I like you videos on the subject but I'm in need of more details on the design and engineering. For example you say it should be designed based on flow rate, which makes sense, but what are the numbers? What is the ideal ratio of pond surface area to flow rate through the intake? Once flow rate is determined what is the ratio of flow rate to surface area of intake foot print? What is the ratio of flow rate to width of intake channel? What is the depth of intake channel? What depth of gravel in the bay? What size gravel? If there are equations outlined in a different video please direct me to that video.

[@KoiAddiction]

No all great questions. There are so many factors that can influence the answers though, it could be an entire video series. Normal practice for me is to design the wetland filter, jets, waterfalls, etc. to come up with a “total flow rate for the feature. From there I size the number of Aquablocks in the intake at 1-2 surface blocks per 1000 GPH of total flow. Depth depends on width of intake, desired flow speeds, potential water level fluctuation, etc, etc. We typically use 3”-6” cobble over the infiltration area so you can “grub” or vacuum the debris from the surface without too much trouble. If you think about flow going into the intake, you can look at our video on the dinosaur pond. That flow in the video is 20,000 GPH and it looks great. Its about 4’ wide and 18”-ish deep. Think about flows into skimmers (speed vs. flow rates) and you will get some ideas on what is possible! Hope this helped?

[@oreospapa]

@@KoiAddiction I'd like to watch that series of videos if you have it. If not, I'd watch it if you produce it.

[@jasonvongsay2620]

@@KoiAddiction Please make an advanced series of videos that explain the factors to consider when designing the wetland, jets, waterfalls. You touch briefly on one aspect of calculating flow rate with the water in motion videos, so I don't think you need to recreate those.

[@budoyrush7144]

That is the NATURAL!!! way of skimming the pond.. No plastic container.. No nets.. No sponges.. Hope to see more projects with these kind of intakes and also with wetland filters..

[@KoiAddiction]

Becoming more commonplace everyday👍🏻

[@cepontzsons]

Great information John...thanks 👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍

[@KoiAddiction]

Hey Pontz! What’s up with you guys? How is life treating youall? I figured I would answer a few messages from 2 years ago😭😂

[@jasonvongsay2620]

First off, you have some of the best pond building videos on YT and I love that your son has taken over the videos. In the video you state that the negative edge filtration needs to be sized correctly, but you don't explain how to size it properly. I've watched several of your videos to see if you explain it, but haven't come across it. What is the proper flow rate? I'm assuming it has to do with the rate at which the entire volume of the pond gets cycled through the filter.

[@anotherplottwist]

Loved the video so much I liked it, subscribed and even downloaded it for future reference. Thanks for the info now to browse your other videos

[@LampWaters]

Thanks. Exactly the information I was looking for.

[@KoiAddiction]

I am glad- hope it helps you out!

[@tanusutomo7031]

Many thanks for uploading this video, it help customer to make decision 👍

[@KoiAddiction]

I hope it helps you sell some jobs!

[@aquascapeponds]

Lots of good information Adam thanks for sharing your knowledge

[@KoiAddiction]

What’s up with you guys? How is life treating youall? I figured I would answer a few messages from 2 years ago😭😂 Hope you are having a great season!!

[@geostorm25]

Great Job teaching!!!!

[@KoiAddiction]

Thanks Geo- mOre videos coming soon!

[@brianliddle3767]

solid information - thank you for sharing.

[@KoiAddiction]

Glad it was helpful!

[@pondkingprojectshowcasesin4124]

Thank you sir! Already made sure my team got to see this.

[@KoiAddiction]

Glad you guys got some value out of this! See you soon👍

[@shadshriver1541]

Great tutorial. Thank you for the education.

[@KoiAddiction]

Is all of that madness helping you at all?

[@schneelutz]

Great Explanation! Many Thanks :)

[@KoiAddiction]

My pleasure :-) glad you enjoyed

[@billthefather]

John! I am so thankful I found your channel! The amount of info you provide in your videos is impeccable! I have learned so much and had so many questions answered already. I feel I have a solid informed plan for our pond now. Definitely building a wetland filter! My family and I are so excited for this new adventure in our lives. Thank you so much for all that you are doing here. I can't tell you how grateful I am.

[@KoiAddiction]

Super thankful for your sharing-it makes all of our efforts worth while!

[@timwood9580]

Great comparison John.

[@KoiAddiction]

I figured I would answer a few messages from 2 years ago😭😂 I try to answer all comments but some slip by…Better late than never ;) Hope you are killing it out there Tim!!

[@TannerFlowers]

Great information! You are the Pond Wizard! Learned a lot.

[@KoiAddiction]

I aim to please! Now I need to do the how-to size an intake and how to properly build and install a negative edge...1 at a time lol. Hope you are doing well!!

[@lifechallenger2]

@@KoiAddiction what should be the size of an intake bay for an rec pond of size 21*15 (5ft deep) with a small wetland filter and a biofall? does size of intake bay matters? and which is an easier maintainance between skimmer and intake bay?

[@bettycorley7369]

I am stoked Bout this content. I have been curious about the differences and it has me rethinking my pond filtration.

[@KoiAddiction]

Well I hope it helped you make an informed decision?? Did it?

[@tristanadams4214]

Sweet presentation! 😊

[@KoiAddiction]

What’s up with you guys? How is life treating youall? I figured I would answer a few messages from 2 years ago😭😂 Miss you dog!

[@vincentdepault9323]

I have seen tons of videos on ponds, and your videos are so informative and detailed. Thank you so much! I'm about to build my dream koi pond soon. 🥰

[@KoiAddiction]

Well I wis=h you the best of luck, I am also about to build my dream koi pond and I know exactly HOW EXCITED YOU ARE :)

[@charlottewilson4560]

Loving your new pointer! Harry Potter in the pond world! Great video I now understand a little more about negative edge and intake bays

[@KoiAddiction]

I love Harry Potter and I did comment about it but it didn’t make the final cut😆Thanks for watching❤️

[@alexline4131]

Thank you so much, these terms were confusing me!

[@ThePondAdvisor]

Love the aqua class ha ha

[@KoiAddiction]

“Studio C” baby! I had fun, feel like Mr. Wizard with my wand pointer😎

[@pondman2513]

Thanks John,

[@KoiAddiction]

I figured I would answer a few messages from 2 years ago😭😂 I try to answer all comments but some slip by…Better late than never ;)

[@jasonlenox914]

Great explanation John G Adams! Many people have made huge mistakes when trying to design a negative edge like an intake bay! We like to triple the water in motion for the containment system. One part equal to your water in motion calculations which includes pond surface. Then one more part to double the water in motion storage in the event of system starts and stops in the events of power loss etc. for water in motion capture. Third part for smooth operations during large volumes of water loss due to evaporation on higher volume ponds at higher flow rates and for debris overload due to lack of maintenance procedures. Many use the wrong size gravel and utilize geotext fabric on top of matrix blocks which can truly be an educational event! Truly cleaning a large system properly with matrix blocks depends on properly designed building with drainage occurrence below the matrix blocks. Again, great video on KZbin John and I hope you do many more of this sort!

[@KoiAddiction]

You are right about all of that. I plan to do a water in motion video at some point in the near future since it seems to be one of the most misunderstood things in the design process and we often encounter ponds and waterfalls that are designed wrong and don't function properly because of it! Cheers!

[@laurens9561]

Really helpful !! I really like your passionate and technical approach. You deserve a lot more subscribers.

[@KoiAddiction]

Thank you so much for your kind words :-) we have been working very hard on producing valuable content for our subscribers and we are just starting to experience growth after 18 months of hard work. We appreciate you watching, and your comments and interaction are very valuable to our channel we thank you for that as well🙏

[@rivercrest-watergardens]

Good stuff John!!!

[@KoiAddiction]

Hey buddy! I thought I would answer you from 2 years ago ;) DO you feel more educated now??? LOL have a great day ;)

[@rivercrest-watergardens]

@@KoiAddiction it is amazing what a couple of years will do for the old knowledge bank!!! Have a GREAT day Brother!!

[@PutsPonds]

Good stuff John...

[@KoiAddiction]

Thanks Dan, keep on keepin on buddy🤘🏻

[@deevpavel]

Хорошее и информативное видео. Реально полезно без лишней воды.

[@KoiAddiction]

My browser did not translate sorry...

[@aquaclearwatersolutions3210]

Awesome! Thanks

[@KoiAddiction]

My pleasure thanks for hanging out with the Adams family :-)

[@paulgroth5414]

Wow this is awesome! I am designing a 2 pond with waterfall on a hillside , trying to figure out the proper filtration, thankyou!

[@brandonvaught5176]

Awesome information. Worked on pond installations and service several years back and am actively working towards my own small pond business here in my area. Your videos are helping to mitigate some of my anxiety. Keep up the great work, makes guys like me excited to be rejoining the industry I feel in love with many years ago.

[@KoiAddiction]

Glad to have you onboard! Keep on changing lives!!

[@PondKingWaterGardensMN]

Thank you for making this video John! It is a great video for me to send to my clients to explain everything. Awesome!!!

[@KoiAddiction]

Absolutely, I hope you guys had a great time in Costa Rica :-)

[@PondKingWaterGardensMN]

Not me sir.. they're just bringing me with virtually!

[@jamiepettitt3708]

@@PondKingWaterGardensMN I live in Costa Rica and am watching this to build a pond. I have cabins on the beach. Let's trade! I supply cabins, materials and manpower. You supply the brain

[@PondKingWaterGardensMN]

@jamie Pettitt I would love an opportunity like that... I am no where near ready... however, this is John Adam's channel and work you're following right now. I know John has experience with working outside of the USA. His work is incredible and he's a mentor to me... try to bring him in!

[@jamiepettitt3708]

@@PondKingWaterGardensMN thanks Nick. I was figuring that John Adam's would be too busy to come to Costa Rica and I see your team has. But Hell yes, if I could entice you John that would just be incredible!!!!!!!!!!!! Modern Design Aquascaping Inc

[@ziggypop123]

Great videos. Would love some discussion about design of both intake bays and negative edges. Long video no problem. Thanks!

[@KoiAddiction]

OK it’s on my to-do list!

[@VPershing]

Thanks for all the effort you put into educating us, John. As a new CAC candidate, I really appreciate your depth of knowledge. One day I hope to shake your hand and thank you in person.

[@KoiAddiction]

Well thank you for the kind words, I’m sure one day we will meet👍

[@trustedSolared4u]

Great info

[@KoiAddiction]

Thanks you make it matter by watching and commenting!

[@shayyourpondgirl4754]

Great info. I see this mistake more then any other thanks for the education.

[@KoiAddiction]

Thanks for tuning in Shay👍🏻

[@musothreads9069]

I liked and subscribe because of the good information...not because you prompted me to.

[@KoiAddiction]

I know I hate asking all the time but you know I don’t get paid squat by KZbin so we have to be shameless self promoters to have a chance on this platform😎👍

[@musothreads9069]

@@KoiAddiction my comment may have been misconstrued due to my wording. I mean to say he didnt need to ask. If the video is informative and useful to me i like it. If the channel is too i subscribe.

[@Littlelamb2023]

😂 i always thought they were the same thing 🤦🏼‍♂ Thanks for this you're a top man 🤟

[@KoiAddiction]

Lots of people have them confused, you are not alone ;)

[@tonymarshall3162]

John … thanks so much for the highly informative videos and your teaching style is spot on to make the info easy to take in and understand ! As a Hopeful CAC in training, I’m a sponge for info ! Hopefully on my way to pro grade level knowledge to be able to serve the clients in my area next season ! This year is all about certification and learning ! Thank you for your effort into these videos ! 💦👊🏼💦

[@KoiAddiction]

Glad to help you on your learning, let me know whatever I can do!

[@johnlambe2912]

Great video liked and subscribed

[@KoiAddiction]

Welcome to the tribe :)

[@premierlawnlandscaping5132]

ITS AN AMAZING WAY TO CLEAN THE WATER I AM FROM NEBRASKA AND TRYING TO LEARN AS MUCH AS I CAN BEFORE GOING OUT TO BUILD

[@premierlawnlandscaping5132]

These are such great videos . I am a landscaper from Nebraska and trying to learn as much as i can from your videos before i go out and build for other people. so keep them comming

[@KoiAddiction]

We will! It’s hard to keep cranking out educational and project videos but we are doing our best to make it happen!

[@stacyadams357]

What an awesome video! And an incredible project! Splitting it into was a brilliant idea… I love all of the “” people plugs. What I mean is like Marti from S.T.I., and then get gas in there, and we got help Scottie and they’re delivering Rock, and Anderson Rental delivering machinery… It made me smile but most of all it’s amazing that you guys can take something like a flat yard that has no character and build it up the way that you guys do I can’t wait to see the finished product🐸 what an awesome video! And an incredible project! Splitting it into was a brilliant idea… I love all of the ““ people plugs. What I mean is like Marti from S.T.I., and then get gas in there, and we got help Scottie and they’re delivering Rock, and Anderson Rental delivering machinery… It made me smile but most of all it’s amazing that you guys can take something like a flat yard that has no character and build it up the way that you guys do I can’t wait to see the finished product 💙🐸💙🐸💙🌻🌻🌻🐟🐠😄

[@KoiAddiction]

It takes a village ;)

[@sieng8]

Thank you

[@KoiAddiction]

You're welcome! Thanks for hanging out with us ;)

[@james660660]

Hi John That was simply an outstanding explanation and much appreciated! I’m thinking that while your full service type customers may appreciate this information it’s especially us diy’ers that benefit. I’ll likely never buy or retain your services up here in Canada, but man do I appreciate your passion and the sharing of your knowledge in your videos. I love the technical stuff; it’s not too common. I’m sure these videos and your efforts will pay off for you. Here’s hoping your business is thriving fella! If your open to suggestions for content; I’d love to see your ultimate design in a similar format; something like your dream pond design and why based on your experience. Thanks! James

[@KoiAddiction]

Im building it right now at home, it will be an entire series!!

[@MrStevebeech]

Would love to add ether of these on to my pond if possible. I currently have a skimmer but love the effect of a neg edge. Thanks you 🍻

[@KoiAddiction]

There is no substitute! I will put one on my pond this year👍

[@kaliebgriffiths9800]

I would love to see a video show how to build both

[@KoiAddiction]

We will be sure to make that happen😎

[@mlock1460]

Good day John, these videos are amazing. What would be the recommended pebble size and layer thickness on top of the aqua blocks in the negative edge design?

[@KoiAddiction]

I like to use 3”-5” stones 6” thick. Just to make sure the blox are protected from the UV!

[@vlive2074]

Thanks for posting the very informative video. Can you also provide some info on what to take care of in terms of overflowing. Power outage happens when there is downpour, so no pumps are working, so how do we make sure that pond is not getting overflowed especially in underground pond ? what kind of special or extra plumbing is needed ?

[@KoiAddiction]

A basic overflow system is fine. I like to use a drain basin set just above desired water level on the side of the intake area ;) Sink the basin outside the pond, drape the liner over the basin, and make a seal. As the water level goes up it runs into the basin & away!

[@keithbassett377]

Hey John awesome info and thanks so much for taking the time to do this stuff it’s really great have a question , if I’m doing a neg edge intake bay in combo with a wetland filter dumping into the pond with waterfall and the water level in the wetland is at a higher elevation than the pond would that water be considered water in motion or would you just put a back flow preventer in the line to the centipede , in a power shut down wouldn’t it flow back into the pond

[@KoiAddiction]

Confusing to me...Water above will flow down when pump stops. I need more info. To understand the situation. Tell me more or we can set up a quick call to discuss!

[@sthomas7211]

I built a negative edge and it works awesome. I have lost a few fish though, and had to play with the rocks to make it less inviting for them.

[@KoiAddiction]

Only the smart fish survive! Usually, in my experience, it only happens in the early days and then they figure it out. The other time I keep my eye out is during the spawn. Sometimes an exhausted female goes over the edge LOL. Have a good one!

[@ColumbiaWaterGardens]

Great video John! Do you use the surface area of the pond x .25 to figure out the water in motion for the neg edge and double that volume for the containment?

[@KoiAddiction]

Honestly it’s a very tight situation figuring surface area of the pond. It really depends how you build the negative age as to how much of the pond water will leak down. My first ones would only leak down an inch or two quickly but then would leak down another 3 inches slowly after the fact. We have learned to manipulate that situation now so that we only lose a few inches. Once we got good at that method, 3 inches of drop is typical. Or larger ponds or higher flows that number increases a bit. After that calculation we double at least if not triple the water in motion For containment. Let’s not forget about streams of waterfalls and all other head-waters being added into that equation as well!

[@ColumbiaWaterGardens]

@@KoiAddiction makes me think about a few things. Thanks very much. See u at pondo

[@columbia2635]

My parents have a pond they've had for decades and I'd like to add an intake bay because of our tree situation. Money is tight...my Dad is 88, Mom 82...so I need to do this as DIY as possible. I've been researching this for a couple of weeks and find very little actual information out there, especially for DIY. Their pond is between 850-1050 gal (not sure about average depth), they have 2 pumps - 1056 & 1299 - plus Clearguard filter. No actual waterfall yet - can never decide on a design - but have one rigged up with a simple shelf & recirculating, and another short one from the filter. Would like to build an intake bay that pumps into a bog, spilling back into the pond, with the 1200 on the filter pumping into the waterfall. The current layout is an oval pond with an 8' stream and the "waterfall" on the SW corner. There is an opportunity to put the bay on the NNE corner, but no room for the bog, so we'd have to pipe over to the south end for the bog. We have good water quality, especially since switching from the TetraPond filter to Clearguard, so a bog isn't so much a necessity as a benefit. I know this is way too much information but that's me! I need to work out as much as possible because of costs and the effort, as I'm no spring chicken either! Just consider this a bid for more info on the Intake Bay! :)

[@KoiAddiction]

Sounds like a great skimmer could be an option for you if leaves are the problem. People often think the intake bay is a magic bullet BUT it just pulls debris into a corner where you can remove it. We just installed a huge intake bay last week and we used a skimmer in the back of it as well. Lots of ways to skin a cat as they say. You may consider an intake with a skimmer or a stand alone skimmer (Aquascape 1000 signature series is my favorite). That will handle flow rates up to 7000 GPH well and will greatly reduce the leaf issues. Intake bay will be more work less frequently if that makes sense??

[@zachthepondbuilder]

I would love to know more about the construction on a negative edge!

[@KoiAddiction]

Will do next time we build it!

[@rivianrs3873]

Great video John. I been watching all your videos and thanks for the knowledge sharing. Your videos always motivates me. I am planning for pond with 10x15x4 . What would you preferer a mechanical skimmer or an intake bay for my pond. I was thinking of both. Skimmer ( 4500 GPH pump) feed the water to Bio filter and Intake bay ( 2600 GPH) feed the water to wetland filter. So during winter I can turn off the Intake bay/Bog filter and the let the other one run throughout the year. Do you think having an intake bay and a mechanical skimmer is too much?

[@KoiAddiction]

For that pond probably is over-kill. BUT- I have fed a wetland and jets from a SS 1000 skimmer and used a small intake system for the jets -the pond is a bit bigger than what you are doing and the water is so pristine ;)

[@jamesdavis-official4936]

John! Absolutely love these videos you are doing, thank you, thank you, thank you! One thing I still can’t seem to comprehend though is the standing surface water after the negative edge in the beautiful koi pond example? How does this work? Wouldn’t the water level have to be buried/lower within the containment basin to allow enough space for runoff if the system was turned off? Allowing all the water in motion to eventually fill the basin? I love the look of standing water/pooling after the negative edge! What am I missing here? How do I make this happen? :) Thanks John!

[@KoiAddiction]

The standing water below the falls in the negative edge can be posed by using a “bib-liner” that is basically a bowl on top of the reservoir. It holds water on top even when the water level in the reservoir is low! The res has to be able to hold at least 2x the water in motion for the entire water feature so it can be costly and also a large part of the project. Hope I answered your question?

[@ourmindanaodream4168]

Great video, makes it hard to decide which way to go. I think for my smaller pond (20x15) the intake bay would be a better fit. Do you have videos showing step by step on intake bay or the negative edge that I can watch?

[@KoiAddiction]

Not yet, but I will show them ASAP

[@ourmindanaodream4168]

@@KoiAddiction thank you

[@HuyNguyen-kt1ym]

Thank you for yours training Jon. I learnt alot from watching your educational video. I just want to ask if want to build swimming pond and koi pond with wetland filter and zero edge. How much does it cost the swimming pond is 28x16 and koi pond is is 15x15 with waterfall and zero edge.

[@KoiAddiction]

That’s totally dependent on location. Near me is one price. California is way more. Other country is even more. If you are thinking of hiring us, reach out to our office and we can chat about it. [phone] :)

[@TheStump29]

Your educational content is invaluable sir. I do have a question. Is there much benefit from making the intake bay fairly deep, to help hold some of that water underground and maintain more stable water temps?

[@KoiAddiction]

If it’s not a negative edge there is no benefit to making the intake deep. If you are going to add extra underground storage I would make the pond deeper OR add a negative edge to get the benefit you are suggesting!

[@TheStump29]

@@KoiAddiction I appreciate the reply. My yard is pretty flat, but I’d love to incorporate a negative edge. How difficult is It to do if you don’t have slope to work with?

[@blucifer9226]

Just when you think you’ve got your mind set up you watch another great video! Negative edge seems to make another nice little water fall into separate pond. With that you’d be able to overlap linings from pond to negative edge correct? Saving to muck with seams or buying an even bigger liner

[@KoiAddiction]

You can for sure. My rule is minimum 12” drop to do over-lap. Bottom liner must go up over shelf and top liner must go down to next shelf. That being said I personally always do the seam these days. Better for long term success.

[@KoiAddiction]

Thanks for your patience on my response- I have been on an out-of-town project for over 3 weeks!

[@blucifer9226]

@@KoiAddiction Excellent information and appreciate the reply!

[@SillySeasonGolf]

John. First, thank you for your videos. They have inspired me to go with a natural swimming pool instead of a traditional one. How do you determine the size of your intake bay including depth length width and how many blocks. I will be building roughly a 20 x 40 natural pool. Any info is appreciated thanks again.

[@KoiAddiction]

Sizing is based on flow rate in intake. Typical intake is. 1/2 - 1 large aquablox per 1000gph flow rate. Minimalist 1/2 per 1000-less maintenance 1 per 1000 gph👍

[@DanLiese]

Such an awesome explanation !!! Your are great !!!! As Tony the Tiger use to say... LOL

[@KoiAddiction]

Thanks Dan!

[@mikehowell9053]

Awesome. Really interested in both of these. Have avideo how made them?

[@KoiAddiction]

Just keep watching, we are making new stuff all the time!

[@davidjamesellis99]

Hello, thank you for the video. I have a few questions. 1. The zero edge receives the water on top and it gets pumped out from below. How does this compare to an werland filter? 2. Can you have both the zero AND a wetland filter? Again, thank u so much for taking the time to create these videos.

[@KoiAddiction]

Yes to #1, no 24” deep gravel bed below a zero edge, just 6-9” deep of 3-5” diameter cobbles for easy cleaning. Yes to #2, that is the absolute best combination 👍🏻😎

[@brentclayton]

Hey Wild, do you have a video on making a negative edge intake bay? Love your stuff from Aus 🤙🏿

[@KoiAddiction]

No not specifically. Really all you need to do is create a normal intake bay that has a small waterfall at the end of it going into a rainwater capture system. The trick is to calculate water in motion and then double or preferably triple that amount in your storage holding capacity.

[@brentclayton]

@@KoiAddiction do you have the same aggregate and blox in it as the wetland filter? Cheers

[@BeckiandChris]

Very informative channel! I’m having a hard time seeing the actual difference in structure of an intake bay vs negative edge on paper. Although I your drawings, the negative edge reservoir is 3 blocks deep vs 1, It seems the only functional difference I can figure out where the water volume/level is at. ie if you ran an intake bay setup with less water, it becomes functionally equivalent to a negative edge? Conversely, adding more water to a negative edge system and it becomes functionally the same as the top drawing? Also, with the negative edge diagram, the water level in the reservoir is lower than the gravel - wouldn’t that make skimming debris/leaves impossible since it would just be solids siting in gravel?

[@KoiAddiction]

The water falls off of a negative edge and has to be designed so the reservoir below is big enough to hold the water in motion x 2 or 3. The intake bay operates inside the pond - no falling into it- the # of blocks is based on flow rates in the IB vs. designed for holding capacity in the Neg Edge!

[@BeckiandChris]

@@KoiAddiction thanks for the reply! It seems like the intake bay would be easier to clean debris since you could skim it with a net, but a negative edge would have leaves and debris just sitting on rocks since the water level is below inside the reservoir? It seems like that would be harder to remove organic material from with it stuck in the rocks?

[@columbia2635]

@@BeckiandChris Can't speak for MDA but my biggest reason for opting for the Intake Bay vs Negative is looks. I don't really have a big enough pond to hide something that seems to be, as you've said, gravel, and would rather have a nice little "pool" where maybe the smaller fishes might swim in and I can easily grab the leaves that make it to the area. I understand the negative edge seems to be more forceful and will do a better job of removal, especially if you don't stay on top of the IB, but I'd prefer to see that cute little pond!

[@djswaterscapesandlandscaping]

Hi how would you work out water in motion plz trying to build a negative edge and want to make sure it doing it right thanks great videos

[@KoiAddiction]

Did you watch all my wim videos?

[@kramrevaew]

Hi from the UK. Love your videos and I have learnt a massive amount. First, I am interested to know if there is a need for a biological filter when a zero edge is used for a 20,000 US gallon pond with 4 fish and two ducks on it. Secondly, I like the idea of the zero edge but the cleaning out of the leaves will be a major pain (I have deciduous trees all round the pond I inherited!) so if I want to use an actual skimmer in the pond for ease of removing the leaves, do I just induce a current and let that do the job? Thanks again, and keep up the good work.

[@KoiAddiction]

How many leaves? How big of a skimmer? If the neg /zero edge is too much work to clean, a skimmer will be sooo much of a pain. This is a rabbit hole, big pond needs big skimmer. Skimmer is less $$- neg edge so much easir😎Just my thoughts

[@bernardovieira9415]

John G Adams, your videos are awesome! So awesome I am designing a brand new swimming pool for our weekend house based on these concepts. We will have it built like a pond and treated with chlorine, so no fish, but the look and feel of a natural pond in our garden. I want to place a negative edge system to collect most of the falling leaves before they get a chance to sink. This will run 24/7 and the water filtration system will run on a timer, according to it's own specific needs. My greatest concern is the dimension of the water reserve. My pool is 105 square meters in area and there is no water in motion prior to the pool. I asked a local pool guy for help on designing the reservoir but I'm really not confortable with the numbers he came up with. He says a 6000 liters reservoir will do the trick. Can we pull it off with just this? To me, he is thinking in terms of negative edges in pools, which is just a fine sheet of water over a long edge. I want more of a cascading effect. Also, how do estimate the pumps to use in order to get the desired water cascade effect. Thank you so much for the great work and inspiration! Cheers!

[@KoiAddiction]

First you need to decide what type of pump you’re going to use or pumps. Then decide how wide you’re going to make the waterfall spillway coming out of your pool into the reservoir. That should give you a calculation of water thickness with a little bit of research. Then depending on how well you build the negative edge, will determine how much water in motion you actually end up with. For me typically I figure 4 inches of water in motion has a safe bet, but this can vary depending on construction methodology and water flows. Now that you figure your water in motion then go two times minimum or three times the amount of water in motion for your holding capacity in the reservoir. Does that answer your questions?

[@TheReviewPigeon]

great explanation. one day i'll convince the wife to let me get a pond with an intake bay

[@KoiAddiction]

That could look more like a trade???😂🤣

[@mrreef2450]

I’d love to see how u properly build both intake bays and zero edges would u make that kind of vide? Thank you

[@KoiAddiction]

It;s on my list, so little time, so much to do LOL

[@danishpatriotwwg1wga291]

Great video 👍 What size intake Bay do I need? I use 2 pump's in my current Skimmer setup, each 20000 liter variabel. 😃

[@KoiAddiction]

I typically use 1 large aquablock per 1000 GPH whatever that equals out to in liters🤣 I see people use less, I have used more-it totally depends on how much junk you want it to hold before it clogs up. More is better to me...

[@ianfoot1370]

Hi John, can you please clarify something for me regarding intake bays? You mention that it makes servicing your pumps very easy and that you can simply pull your pumps out of the water, but surely the pipework that feeds them, travel through the wall of the intake bay and as such prevent the pumps from being lifted out. Many thanks Ian.

[@KoiAddiction]

Yes, you still have to open (access) vault lid and disconnect the unions to remove the pumps but it is much easier to do than in other situations…

[@wildgfygal]

I want to make a intake would love more info

[@chadnoland4404]

Do you have a detailed Video on building and design of an Intake Bay?, Thank you

[@KoiAddiction]

No but I am going to very soon!

[@philippefenain4405]

Hi John G. Do you usually install an autofill in your intake bays ? How is this done ? Thank you very much.

[@KoiAddiction]

Yes- if I do I use an extra pump vault for it!

[@Sztrovacsek81]

Great video! Can you cover the top of the negative edge intake bay with an extra overlay + sand on it? I'm planning a sandy entrance for my children and I think the negative edge area would be suitable for this. Thank you.

[@KoiAddiction]

This is a very “high-flow” area, I would think that your sand would end up in the reservoir bottom and cause a mess…If you can figure out how to stop that from happening you are good. It always seems to migrate down though. Heavier sands are less problematic but if it ends up in the bottom, it will be a constant maintenance nightmare for you to get it out.

[@Sztrovacsek81]

@@KoiAddiction Thank you! I think I'll stick with the intake bay + sand combo. There is not a huge drop of water, maybe it's easier to keep the sand on the top of the filterbed maybe with 2 coats of overlay geotextil.

[@KoiAddiction]

Sounds good, let me know how it works so I can share it with the world, that’s how we all learn TOGETHER! Have an awesome day ✌️

[@Sztrovacsek81]

​@@KoiAddiction I was thinking about it and now I'm afraid that the 2x300g geotextile could hold the sand but would grab all the dirt, and it'll accumulate between the sand and the geotextile. So no dirt will be trapped at the bottom of the intake bay. What do you think?

[@hansvanakkeren6021]

Hi John How about explaining how to add a proper zero edge skimmer to an existing pond would the set up be more or less the same as a wetland filter but in reverse ( flow ) What would be the proper sizing in relation to surface area Thanks in advance for your help

[@KoiAddiction]

Watch our water in motion videos. After calculating your water in motion for the entire feature, double that (minimum) for sizing the reservoir below the zero edge. The reservoir is the same setup as in a pondless waterfall after that!

[@huey8431]

Great informative video. I'm in the process of building my pond and like the concept of the intake bay where it is a part of the pond. I am limited in space (10' x 8' x 3'). What are your thoughts of an intake bay feeding a bog filter and an under gravel filter bed being powered by an airlift system and dispensing the oxygenated water back into the pond? Any insight would be greatly appreciated. Thank you.

[@KoiAddiction]

Never tried that aeration system in a pond, only in a fish tank but it sounds cool. I like the intake bay but I prefer a skimmer on a feature that size, easier to clean and maintain. We have done beautiful ponds with skimmer / wetland combo👍

[@huey8431]

Thank you for responding and giving feedback. Ok. I will do the skimmer with a bog combo for one piece and the airlift powering the under gravel grid

[@simsdewayne1297]

How do you determine size and build a negative edge filter

[@julientomasi3174]

Hi, thanks for this very good video. For the next one, I The music could be softer=-)

[@KoiAddiction]

Noted!

[@philippefenain4405]

Hi John, Thank you very much once more time for this video. With a negative edge or an intake bay I wonder 2 things: 1) how good is it in filtrating very small debris since with pebbles it can only trap “larger” debris like leaves but pollens and real small debris will go through? 2) some of the debris will go through inside the Aquablox and sediment there. How do clean that area when needed ? I also wonder why in the Aquascape world you don’t use sieves as mechanical filter. It does trap debris much finer than a skimmer, an intake bay or a negative edge would do. What is your view on this ?

[@KoiAddiction]

The design/ flow requirements in the wetland are based on “de-sedimentation” of the water as it disperses out in the bottom of the filter. You can see that from our large pond videos it is working. You can always improve on things. Smaller gravel - slower water etc. but each of these changes will effect other things in the system as well such as clea ability and dissolved oxygen levels. I am working on how to clean a wetland filter on a pond for next year. Bottom of pond wetland NOT my7 first choice-even though plants are a benefit to the filter they are not necessary for biological filtration to occur. Bottom of pond filter requires the pond to be emptied for filter cleaning Which is why I don’t prefer that way. We don’t backflus a wetland in a pond until it is emptied- if the wetland is separate you can clean it without disturbing the pond at all!. Thanks for the interaction ;)

[@LampWaters]

Is there a video to size my intake bay? Water depth, depth of weir, width across bay and width across intake. I had hope a 2x2 or 2x3 ft bay at 2ft deep would do for my 11x26 swim pond

[@KoiAddiction]

I use a small aquablock per 500-1000 gallons of flow for infiltration of water in intake. Weir depth is wide open- make it larger and you can block it- make it too small yer screwed!

[@tedmihalca]

I would rather install an intake bay/ wetland filter to any feature vs a skimmer/ biofall!

[@KoiAddiction]

Yes- but on a smaller pond (in TN) I find skimmer and small wetland to be the best combo for water quality.

[@luudantu7211]

For intake bay size, you mentioned that it depends on the flow rate. Is there a formula to calculate for it and would it help to build it larger than that size?

[@KoiAddiction]

Yes sorry for delay…we do 1 to 2 large aquablocks per 1000 GPH flow rate, 1 on a easy access, no leaf problems, regularly maintained feature and 2+ if it is commercial etc.

[@Lady0Reynolds]

I know the sideview was meant to show all the layers and waterlevel and stuff but looking at it this way made me wonder: is it feasible to have an intake bay as a part of a rocky beach to walk into a recreational pond? like, there's the edge of rocks that's sometimes/often dry, then some ways in there's a hidden belt of the intake bay, and then the rest of the pond? Just a fun thought I'm wondering. I keep seeing the intake bay as some separate little pool, which is fine, but this could be an interesting take...

[@KoiAddiction]

Yeah we actually just worked on a project with a American Aquascapes in North Carolina where they did exactly that. I have done it on a small scale before and used a small Riverstone beach area as the intake. I just prefer to pull all the crap further away from the pond instead of collecting it right in the edge. It really depends on the circumstances the water feature and its surroundings on whether or not that would be a good idea or a lot of work...

[@gielmathijssen2741]

I'm planning to have a stream out of my main pond, because it is situated higher. If I understand this correctly, that will function as a zero edge, so I have to have a overflow/ storage in de bottom pond in case of a power out to keep the water in motion in?

[@KoiAddiction]

You are correct!

[@johnhildebrand8740]

What do you recommend for the depth of the water flowing into the intake bay?

[@KoiAddiction]

Depends on -does pond level fluctuate? Adjust accordingly-do you want to clean intake without draining? -How much flow is there? Many variables, but 10” of water above gravel as a rule for me-width is also important and will improve your skimming ability if depth isn’t so important👍🏻

[@fordguyfordguy]

John, is there a rule of thumb for calculating the volume of my negative edge storage volume?

[@KoiAddiction]

Check out our videos on water in motion. Once you know that we go 2-3 x water in motion for reservoir volume!

[@Photomomlove]

What if the water level in the main pond drops below the drop off, is the the pump hooked up to a shut-off valve?

[@KoiAddiction]

The water level in the main pond stays constant. Think of a sink full of water with the faucet running (waterfall). The water level in the sink remains constant, it only over-flows as the water from the faucet pours in. The pump is in the lower reservoir (below the sink), it returns water through the faucet up top. The water level below is all that changes. If the pump runs out of water below (reservoir) runs out, the pump stops, as does the over-flowing of the sink. The entire time, the sink stays full to the over-flowing level and the level of the reservoir is the only thing that CAN change! If the reservoir is properly sized (and / or) it has an auto-filler installed at the proper level, you will be good. We good??

[@Photomomlove]

Is there a formula on the optimal flow out of the main pond? I have taken some videos that discribe my problem. My negative edge basin keeps the water level too high in my main pond. Ugh. I need another opinion.

[@KoiAddiction]

I have “created” that problem before. I had to tear out the negative edge and lower it / rebuild it. My mom always says “It’s cheaper then college!” ;)

[@WarMarsM]

This might be a bit off-topic, but I'm converting a ~20,000 gal concrete-lined pool into a pond. I'm planning to cordon off a section of the 3ft deep shallow end into an intake bay. How should I construct the wall separating the intake bay from the rest of the pond? I'm thinking I'd use rocks and mortar, would that be suitable? Also, should all of the water be flowing through the intake bay or should I have another intake somewhere deeper in the pond?

[@KoiAddiction]

I would just put liner on the bottom and then rocks on top with some mortar would be overkill. The downside would be that you couldnt drain the intake without draining to the bottom of that section (this design is water resistant design-not waterproof). The upside is ease of design and installation and it works just fine. Use stones on top to hold up liner and the on other side as well using gravel to fill between-basically creating a dam to restrict water flowing by. I like to pull all flow through the intake personally.

[@jameshiestand400]

Are intake bays and negative edge filters used often in conjunction with wetland filtration systems? Is it redundant? or do they compliment eachother?

[@KoiAddiction]

Absolute compliment! They work together👍

[@aflockofseacowsesquire]

what keeps the fish from going over the zero edge and getting trapped in that area?

[@TylerTervooren]

John, my excavator is coming tomorrow and I had the brilliant idea to redesign things to include an intake bay at the last moment instead of a skimmer. I have 2 questions if you have a moment. A skimmer has a door on it that kind of self-regulates the level of water that is being skimmed as the pond level rises and falls, right? That won't exist (unless I design something brilliant...) on an intake bay. If pond level rises, you're skimming more water. If it falls, you're skimming less. Also, a skimmer weir has a fixed width. What you see is what you get. But you have to design your own width for an intake bay. So, two questions: 1. How do you maintain optimal skimming effect as the water level rises or falls without that self-adjusting door that would come with a skimmer? 2. How do you decide how wide to make your weir? Should I just copy the width that would come with the skimmer system for a similar sized pond? Thanks for any advice you can offer. If it gets too complicated for me, I'll just go with a skimmer and be happy I finally have a pond.

[@KoiAddiction]

Wow that’s a tough one, I am a fan of an intake bay but honestly if you’re not exceeding your flow rating for a skimmer it’s easier to service and clean. You need to be careful when you build your intake bay bay that you don’t make it too deep and wide because it won’t do a good job of skimming. On the other hand you have to make it deep enough to accommodate whatever water level fluctuations you intend to tolerate. It’s not super complicated but I have built a beautiful 20 x 20 pond that’s 3 feet deep with a wetland filter fed by A skimmer. The intake bay is a great concept but it’s not right for every situation. I would say with an Aqua Scapes 1000 scammer if you’re only pulling 8000 gallons per hour the skimmer is the better bet.

[@TylerTervooren]

​@@KoiAddiction You're a legend, John. I'm estimating about 7500 gallons, so a little on the margin. But as long as I don't grow an affinity for koi, I think I should be safe with a skimmer.

[@KoiAddiction]

You can also just use pondless vault with 6 small aquablocks to make a small “intake” area next to the skimmer and then put an aquasurge 5000 in there. Use that to feed 5 jets and your good. By placing it near the skimmer you enhance the “skim” without overloading the skimmer. Feed your wetland from the skimmer and all is good in the hood🤘🏻😎

[@TylerTervooren]

@@KoiAddiction Never even considered combining them. Why not? Makes perfect sense.

[@KoiAddiction]

Do it🤟

[@Brad-lt4lw]

If I understand correctly the negative edge system is basically used just a skimmer section for the pond and the water is then pumped to the wetlands filter?

[@KoiAddiction]

That is correct! It is a big-fancy skimmer at the basic level, even though it brings so much to the project!

[@BaruchDavidGreenman]

VERY INFORMATIVE! I learned a lot. I don't understand why those filters aren't creating biological filtration. If those are Aquablocks covered with gravel why isn't it a form of biological filtration?

[@KoiAddiction]

They are in fact creating tons of biological filtration. The intake bay obviously has much less surface area but the biological filter up top (also called an upflow wetland filter) is designed with specific flow rates per surface area to encourage amazing biological filter activity that is easy to clean and maintain!

[@BaruchDavidGreenman]

@@KoiAddiction i understand. In an area with lots of leaf fall would these systems require daily maintenance? More than an Aquascape skimmer?

[@KoiAddiction]

Depending on solids, they can handle so much more material than a skimmer. At certain times of the year it may make sense to create some sort of a net that you can just lay in the bottom of the intake so that you can simply pull it out to dump the leaves and then replace it. It is definitely created with the intent of being a mechanical filter. The purpose is to gather all debris into one easy to access location where you can physically remove the debris.

[@BaruchDavidGreenman]

@@KoiAddiction Thanks for that clarification. Other pond builders in Israel say that an Aquascape design would not work well here due to the tremendous amount of dust we have in the air from the Semi arid /desert environment. Would an intake bay and a Wetlands filter be the solution?

[@KoiAddiction]

I don’t see dust being an issue with this filter system at all. If the dust collecting on the surface of the water tends to be the problem, the negative edge system will handle that by skimming it off. The wetland filter should have no problem capturing the dust though you may have to clean it more often depending on the amount of material that it’s capturing. If the dust is extremely fine and is staying suspended in the water periodic additions of flocculant may be the silver bullet. I would also ensure that the water flowing up through the wetland is slow enough that the particles can fall out of suspension, You may have to stay more on the low side of the 1500 gallons per hour per centipede module👍🏻

[@Photomomlove]

Where can I find some of your negative edge designs? I am digging next to my pond as we speak, not quite knowing how it will all come together.

[@KoiAddiction]

I always design for each feature, follow the water in motion videos to get the proper size and then you will know what to build. Does that answer your question?

[@mattrapplean448]

I would like to know how big i need to make my negative edge on my pond. It's going to be 24x22. 7ft deep to 4.6ft deep. I also need to know wetland filter size.

[@KoiAddiction]

You can use our “water in motion” videos to help you calculate reservoir size. I make negative edge Ass wide as I can so fish don’t hop over. If you have room, make a stream between the res and the pond. I like to go 1’ of width per 1000GPH flow but you can do 2000 GPH per foot if you have to (go longer stream then). If you need more help just call our office and Nina will discuss options. I can help you if needed :)

[@williamm6464]

Can you install a negative edge and a separate bog filter?

[@KoiAddiction]

Yes - negative edge from the pond- wetland filter beside negative edge reservoir!

[@johnhildebrand8740]

John - I have a question on your auto-fill in a pond with a negative edge. My assumption is that your auto fill is in the negative edge reservoir at some depth you determine as a minimum water level. Is that correct? How far below the top of the gravel do you usually put the Autofill? Thanks - JH

[@KoiAddiction]

Fill the res, plug it in, when it is in circulation then set auto-fill just below that level in the res ;)

[@johnhildebrand8740]

Modern Design Aquascaping Inc. That is what I had figured. Thanks for the confirmation.