What are pH, EC, TDS, and PPM and How Are They Connected?

If you're new to hydroponics and have NO clue what all of the terminology means, this video is for you. Even if you're an intermediate grower and want to know what EC is, what TDS means, which you should use, and how it all connects to pH, make some time to watch this one today.
The truth is that EC or electrical conductivity is the purest way to measure your nutrient concentration. TDS or total dissolved solids is a calculation based on EC that meters perform internally. TDS is measured in PPM, or parts per million and the calculation can vary based on the conversion factor.
This is why you must know the conversion factor your meter is using if you're using TDS. Or you can simply switch to using EC and never have to worry about it again!
Today's video is sponsored by Apera Instruments, makers of water and soil testing probes and meters. They kindly donated the PH20 and PC60 meters for me to make this video.
IN THIS VIDEO
→ aperainst.com/
→ PH20 pH Tester: amzn.to/2hKrBEM
→ PC60 pH/EC/TDS Tester: amzn.to/2z9YfGQ
SUPPORT EPIC GARDENING
→ Shop: growepic.co/shop
→ Seeds: growepic.co/botanicalinterests
LEARN MORE
→ All Our Channels: growepic.co/youtube
→ Blog: growepic.co/blog
→ Podcast: growepic.co/podcasts
→ Discord: growepic.co/discord
→ Instagram: growepic.co/insta
→ TikTok: growepic.co/tiktok
→ Pinterest: growepic.co/pinterest
→ Twitter: growepic.co/twitter
→ Facebook: growepic.co/facebook
→ FB Group: growepic.co/fbgroup
DISCLAIMER
Epic Gardening occasionally links to goods or services offered by vendors to help you find the best products to care for plants. Some of these may be affiliate links, meaning we earn a small commission if items are purchased. As an Amazon Associate, we earn from qualifying purchases. More info on our process: www.epicgardening.com/disclai...

[@paulbaker4248]

Great video. Forgot 1 little thing about the pc.60. When reading ppm's. It will automatically switch from ppm to p.p.t. ( parts per trillion ) if your reading is above 999 ppm. To convert? Take the p.p.t number. Multiple by 1000. There's your ppm number. It will switch over. So be aware of what the reading is on. Happy grows people 😂

[@janetw8294]

Product advertisement aside, the beginning of this video was by far the clearest explanation of EC I've found on KZbin. Thanks!

[@JDean-oe1ux]

Thank you, thank you, thank you! I went to so many videos trying to find a clear explanation for EC and TDS and every other person made it made it seem much more confusing than it had to be. I'm only 4 and a 1/2 minutes into your video and you've already given me a much clearer understanding of what these things mean. You are explaining the information technically, but also clearly explaining those things that are specifically important to a grower. Much appreciated!

[@SirLaurenceII]

By far the best explanation I've seen on what and how to use the testers. I have done a lot of research and readings on that is the best way to check the solids on each hydroponic solutions, and there are a lot of conflicting ideas, until I've read about using EC instead of relying on TDS/PPM. Your video reinforced the need to focus more on reading the EC, and I am totally sold to that idea. Thanks a lot, I really appreciate the information.

[@oldmanobie6300]

I've watched a dozen videos on this subject and yours is, hands-down, the best one. I realize this is a 4 year old video, but I hope you see this comment. The only thing it was missing was the proper readings for various vegetables.

[@romandraven7689]

Wow. Amazing. You just taught me the whole reason you Ph in just 3minutes. That's something I will remember forever thanks man. I'm subbed.

[@Blackfarmercouple]

Idk how you got it in 3 minutes because I didn’t realize there interconnectivity between all of these measurements. I hit a new level learning ph, hoping that learning the rest of these gives me a new edge. Also Gonna sub✊🏽. Happy growing all

[@balasubramanianjayaram6228]

Very informative and excellent information. I had been so far depending on pH and TDS gadgets only, and at times used to doubt their readings. Only after seeing this video, and the pc60 meter, I get a clear picture. Thanks a lot.

[@dumitru3355]

What are you using this for?

[@chrisbee9164]

I am so glad that you pointed out not to touch the black sensor rods when putting the PC60 into the soaking solution and NOT to fill to the fill line ! A good video man, well done.

[@montanateri6889]

But I would wonder if those two are still true, as the video is 5 years ago and we no longer have to calibrate the meter, so I'd think those two points would have changed by now. My meter doesn't say anything about not touching the rods or to to not fill to the fill line...

[@a6asics993]

Thanks for posting this video. I just purchased the PH20 meter, and got thru the calibration thanks to this video.

[@epicgardening]

Glad to hear!

[@stewartohana5]

I have been googling like crazy for someone to HELP me with the salinity meter that I purchased from Amazon because the directions that it came with was crap! Your video covered my questions and much more. Based on depth and breadth of this video, I feel empowered to live my best life. 🤙

[@shirleyprentice3774]

Thanks I could not get to grips with the instructions, You have made it clear to me in minutes .

[@destitute8493]

Voice sound for men is usually 1000 - 2000 Hz. Use an equalizer to reduce the background music in that range so it doesn't interfere. In general instrumental music without voice is preferable.

[@tz9735]

I have just begun the venture of trying to decipher all of this in order to add CaliMagic to my Orchids and Violets. I want to say thank you for this informative and interesting video. I now have a better understanding of what it all means. Prior to watching, I'll tell you that my head was spinning because of watching other videos of people making their solutions to fertilize and discussing PPMs, etc. I didn't know what it all meant. Whew, I almost gave up! My next step is purchasing a meter and then figuring out how to use it in order to achieve the proper ratios for fertilization. Thank you again. You did a fantastic job!

[@epicgardening]

No problem! Thanks for watching and glad it was valuable to you

[@yolilopez1992]

I still haven’t figured it out. I just need understand if meter is calculating total ppm even though I clear each reading⁉️ I would rather have spoonful measurements ‼️

[@lionelperez6635]

Bro ... Great video.....definitely elevated my learning curve now ... Gracias

[@denish8905]

thanks for putting me on the right track and imparting a clarity

[@epicgardening]

Happy to help!

[@KevanArt]

good info. I want a video that demonstrates the steps from testing a solution to ammending it based on the reading.

[@thedutchman4205]

dude finally an easy to understand explanation of this stuff..thank you

[@epicgardening]

Happy to help

[@rhysmartin6967]

Man, you would be the first result that I found useful when I searched tds plants. CHEERS

[@natefidalgo7625]

Very good explanation. I was familiar with pH testers , pH up / down etc. But was a little confused about the EC and tds tester/ meters and what the difference / what to go with. Now I am ok with it. But have additional one question above

[@phillipparkhurst619]

this was an exceptionally educational video... thanks for your hard work !!

[@epicgardening]

Glad to hear, no prob!

[@HogdaddyGlenn]

Thought the video was very informative...for you folks who had problems with the music...realize this young man gave a stellar video. Lighten up folks.

[@michelbillen9233]

Very good info, nice and clear, thank you so much!!

[@MrAmjad080]

Very informative sir thank you very much...

[@bryetube86]

Still works in 2021. Love it. Thorough video.

[@revy_moto]

Very interesting, would love if you just went around with this testing the water that your plants are using. Then commenting on how to get the correct ph levels.

[@royal4233]

Some nutrients have a set ph level and if the ph is off just buy some ph up and down

[@loririley3171]

That was the best instructional video...I subscribed. Looking forward to following your channel

[@chrisluehr3256]

great vid need more. i did not notice the music i was paying attention to the info being given. u rock thanks growmie!

[@victorb145]

I like the fact that you can choose the conversion factor in TDS mode. I will look for this when I upgrade my meter. It annoys me to think that friend Sam might have a meter that uses one conversion but Tom's uses another and John's uses yet another conversion. It's a function I always wanted but didn't know some meters are capable of it. Have seen this video before I don't know how I missed that but now that I can add it to the list of considerations this video is getting a like if I didn't give it one already.

[@Chandra-Google]

Thanks a lot for your information. its very detailed and in simple way......once again THANK YOU...

[@alinemcfadden2564]

Very good . I like extra information about nutrien and why pepper stay small in hidroponic systems

[@epicgardening]

Awesome, thanks for the feedback!

[@Rews-fishshed]

Very helpful video, had to take out my pc 60 and redo it after this because I was a bit frustrated with it now i will start using again thank you

[@kenmartin7711]

I am building an aeroponic garden. It uses a reservoir of nutrients and misting nozzles that draw solution from the reservoir and create a mist in a root chamber. The reservoir has a circulation pump that pumps the solution through a chiller and a heater which keep the solution's temperature constant. The mist in the chamber drains to waste. New nutrient solution is added to the reservoir each day to replenish what was used. The pH of the new nutrient solution is adjusted to keep the pH of the reservoir between 5.6 and 6.0. For several months this worked well and the pH remained stable from day to day. Lately, the pH begins dropping and over a 24 hr period can go from 5.8 to 4.9. I do not understand what could be happening as nothing should be altering the solution. BTW the nutrient solution begins with RO water, then adds CaliMagic and the Flora series of nutrients from GH. pH: 5.8; ppm (500) of 600.

[@nastytechniquez9685]

Thanks for the explanation on how ec is the baseline and ppm is measured off that number. Nobody mentions this and it’s HUGE!

[@porterrock4515]

I love you videos you explain everything and make it simple thanks

[@Spiritualwarrior-mh4gu]

great topic and video very easy to understand thanks!!

[@robparla5513]

my man giving the knowledge. awesome

[@user-is8zx9ou8h]

Finely explain about this stuff, exemption about EC TDS and PPM.

[@travisgadbois3417]

you have no idea how much this video helped!

[@gyanmudaliar6598]

Very well explained

[@smarthought]

Great explanation

[@joesoutdoorplaces]

As a beginner I am confused about EC. I mix my nutrients by the directions on the label. Why is it important to know EC if you mix according to the label? The only thing I can think of while awaiting your answer is this. If my plants are growing in, for example, a Kratky solution, they will use nutrients from the water, lowering the EC. I can use the meter to add nutrients to get the EC level back up instead of replacing the entire system with freshly made nutrient solution. Is that correct? But there still remains the question of what nutrients are being used. Is the plant using more nitrogen? More phosphorus? More potassium? Or, maybe being a beginner I am not aware that N,P, and K are being used at the same rate, of course, depending upon the ph. I hope that I am asking my question correctly. I am happy that my gardening is just a hobby and my life or bank account does not depend on knowing all of this. Thank you.

[@epicgardening]

I find it always important to know the principles behind it, so I can solve any issues that arise instead of relying on the labels. As far as your question of individual nutrient usage, you're right in that measuring EC/TDS/PPM doesn't give you that answer. That's why it's important to do a full flush of your system and use fresh nutrients once a week so you 'reset' the amounts, in case your plants are depleting one too quickly (nitrogren in vegetative phase for example)

[@pcjpcj4070]

I know this was 3 years ago but, if your using RO water it doesn't make much difference. If you use declorinated tap water thats high in tds, your ec will be higher which where I live tds is at 598 ppm. So if I push what the manufacturer recommends, its way over and causes nutrient lock out.

[@nancybowers7951]

Thank you. This is what I was looking for.

[@hanna_hydro2393]

Great explanation!

[@ChumpyChicken2]

Hanna_Hydro love the 98131 guy’s!!

[@thomasswenddal772]

Wow Kevin, you really out did yourself with the nerdy stuff, but I stuck to it to the end. I'm a learner too and you're and honest teacher. I've found some great growers on KZbin hardly check these things at all and some measure and record every little thing. It would be interesting, not that you'd update this video but, to ask your future interviewees how much attention they pay to these measurements and modifying practices. Just a thought. Love your stuff, even got a Birdies 30" raised garden bed for my first year in gardening. (Wonderful product, thanks.) But I hope to be able to grow in both soil and hydroponics technique. Thanks for the class. : )

[@ARR87]

Good explanation much appreciated!

[@parvizesfahani5924]

Excellent video. Thanks for sharing

[@lepayen]

Cool. I found these 2 meters in the trash, they both work but I didn't know what the TDS&EC one was except that it shows me PPM, now I know what they were intended for, you explained it perfectly..

[@FXShroud]

Thank you for the vid, Eric!

[@ricks2907]

Great content thanks

[@David-xw9zm]

Love the video . explained very well . music in background distracked me . great job !

[@yvencia1150]

Great video and thank you for sharing😊

[@kenmartin7711]

Nice job. I learned a lot

[@epicgardening]

Thanks Ken!

[@constantine8601]

the best explanation which I could found

[@epicgardening]

Thank you!

[@icycoldtouch8607]

Probably the best vid on this subject I have seen

[@SuperHeroSewing]

I have a new and huge hydroponics tower with 27 ports for plants. I was having a devil of a time finding out COMPREHENSIVELY, including calibration, how to use my Apera PC60 (so lucky I chose this from so many choices). I've been subscribed to both channels for ages now, Kevin, all tremendously useful, and this video is the most important one of all for me so far - I can now go forward confidently!

[@rgrea2]

Just WOW and Awesome content and just what I needed to know I'll order the PC60 from you link

[@epicgardening]

Glad to hear!

[@jessegames6714]

Thank you, Great Job.

[@epicgardening]

Thanks dude!

[@KevinBakin365]

Thank you, sir!

[@Deepgreenclean123]

Awesome video well done...

[@powerbull5109]

Very helpful

[@ZiaurRahman-yk9qi]

Nice information

[@powerbull5109]

Thank you for the video

[@desiera690]

Very informative 👍

[@budj13]

This is an excellent video of very important and useful information for those of us venturing into hydroponics. I know this was a lot of work so, thank you. The explanations were great. The product details were interesting but less important to me since I already have different meters. The background music was a bit distracting. Keep making videos for those of us who like you are learning gardeners. Thanks!

[@odinwoke6787]

Great content.

[@ahapainenpaavo6010]

i have nothing else to say except that this is a really well made video. A+. I don't think i missed any info. I'm pretty sure that I learned everything there is to learn about this subject.

[@alirezavancouver]

Thanks man, Great video

[@Playingwith3D]

I have the same meter, only an older model. I would suggest that Apera Instruments mold the measurement lines into their calibration vessels as the printing wears off pretty fast.

[@brianpimental2948]

Thank you great video

[@rukshanthajanaka9470]

Very good stuff, love you man.

[@epicgardening]

Love you too

[@firdavsmutalipov7479]

Thanks sir. So informative informations.

[@aketipoki2517]

That is cool..alot of callibrating though..Thankz..

[@bkilpatrick1909]

You are far from a learning gardener, I love your videos and that you are a MAD SCIENTIST. WISH I had the price for the PC60 Meter. I'll Google it, and again you did a great video. Keep teaching me.👍🌱🗣

[@epicgardening]

Thank you my man

[@bkilpatrick1909]

Your videos mean more than you know because I use them for me seizure disorder so I don't have to worry about paying 57.00 dollars for a 3.5 from one of the Dispensers down here and I have learned more from you than the Masters degree from THC UNIVERSITY with a 94.8%GPA lmao. Thank You Very Much Again. Have a great night.

[@evolveausevolveaus]

Good vid thanks for the test/ ppm info 🤓🇦🇺

[@kirtikumarpatel9482]

Nice.Can you explain EC required for various crops please?

[@epicgardening]

I'll do that in another video!

[@Janedeereusa]

I just bought this pen, thank the high spirits you made this video, I feel confident using this now!!!!!💃🏻

[@andyc.2260]

Loved the content. Made something very very confusing into some very less confusing lol. Thank you. Can you do more videos about this topic and how it effects your hydroponic plants?

[@jennhoff03]

;'D Very less confusing. ;'D I like that!

[@timendbig1]

Swe👍🏻❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤😀❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤ 18:09

[@timendbig1]

Hi

[@timendbig1]

I think I figured it all out

[@timendbig1]

As long as I replicate these exact situations

[@fortedexe8273]

Amazing video, thank you. I just want to ask at the end of video, when testing floramicro, how EC can be 600 mS, is EC should be like 2.0 2.5 or something ?

[@henrysaw3091]

He is talking about μS (microsiemens) not mS (milliesiemens). What he was talking about 600 iwas μS... So 600 μS. 1.0 mS is equal to 1000 μS. So 600 μS is equal to 0.6 mS.

[@DaveyBoyxxtha1Nonly]

Great video, came here for EC and this was super helpful.. i just found it hilarious when you named all 4 units and said both the abbreviated and full versions and when you got to pH you just made a face LMFAO

[@teestrees5839]

Potential hydrogen, he forgot it 😆

[@dan.m.5209]

thanks for the video . I learned a great deal a lot i did not know so thank you

[@khalidjaii2]

Do you have another video on this topic, but without Music? I am too old to focus on complicated terms with loud music 😥

[@woody3476]

9:23 nice save

[@JaniceCrowell]

The background music is too loud and making it very difficult for me to concentrate on this important information.

[@mawamatakama5150]

I second this. Get rid of the screams that you call "Music".

[@abdallaakoud1166]

Very Informative - thanks. Now i know why my hot peppers are suffering from over feeding. Can you explain please the optimal EC/TDS for super hot peppers. I am maintaining a pH of 5.8 - 6.2 for them but my cheap TDS meter reads 1463 - how bad is that

[@epicgardening]

Seems OK, you probably just need to dial it back a bit to maybe 1000 or so

[@SEXYTECH1000]

THANK YOU SO MUCH, AWESOME AND EXCELLENT VIDEO ,

[@Senju2dbone]

What would be a good EC for tomatoes?

[@dsayers586]

THANK YOU

[@406findings]

Growing in soil so should ppm be something I should watch?

[@DJTechnoboom]

that was a good video thanx

[@vijaykumarparekh8596]

Excited

[@brucewarren9281]

"...ppm, parts per million. pH, ..". lol so funny

[@eugeniovazquez7444]

Nice Video 👍 Nice TDS/EC meter. I wish it can measure N , P & K individual. So I know how much of each individual fertilizer I need to add or stop adding. I’m not really good at identifying plants deficiency by looking at the plant, but the ph tip is very helpful. Been struggling with my plant tank , my plant are die & my ph is high 7.4 ph , now I have to battle my KH just to keep my ph in checked/stable . Any tips or suggestion is well appreciated. I love looking at my plants in my Fishtank

[@epicgardening]

Hard for me to give suggestions about planted tanks, i'm not as experience with aquatic setups! pH down and constant monitoring might help

[@atomizer2665]

If you run a drain to waste system you will always know the elemental content of the nutrient because it doesnt change.

[@montanateri6889]

Kevin is the first video I've seen that puts all this into plain english. My meter (purchased in 2023) says"TDS/EC Meter",. then doesn't have those 'name' shown on any readings. Instead it shows numbers for "ppm" and "us/cm" (the u is funny looking, so it isn't a letter but a math symbol.) So after reading tons, and watching this vid like 4 times (cause I'm not into calculus), I've finally figured out: 1) TDS shows on my meter as ppm, which is converted inside the meter from the EC value at a conversion factor of 500 or 700 or 570, and who cares because we don't need it so ignore the TDS/ppm just like Kevin says. You can't use any chart online to equalize that to a EC level without knowing the conversion factor your meter is secretly using so skip that number completely. 2) The us/cm is EC in microseimens. Convert that to milliseimens by moving the decimal over by 3 points.... So 1230 us/cm converts to 1.2 EC. And that is the number you need. (so a 800 us/cm would be 0.8 EC If you had 870, round up to 0.9 EC) Find a chart online that you can copy into Excel or print out, that shows you what EC is needed for each type vegetable or fruit: Like strawberries need EC 1.8 to 2.2. Peas need 0.8 to 1.8. You only use the TDS/ ppm to get a EC value, and your meter already gives that to you nowadays, it just doesn't 'say EC, it says us/cm .........because math people love to complicate our lives. So ignore the TDS/ ppm completely,. Just like Kevin says in this video. For PH... do I sound like someone who wants to calibrate a ph meter? No. I bought little water test PH strips. Works great. 😁🤣🤣

[@willfullyinformed]

Curious, I keep my PH at around 6.0 - 6.5 using lemon (more stable than expected); it was easy to bring the PH down from 8.0ph as my water is through an RO/Carbon filter that's enriched with natural calcium chloride. Currently my PPM is about 220, I've read around about this being too low that 500-1200+ ppm range is best for vegetable plants in vegetative stage. Is this true about vegetables? Also, what do you recommend organically to raise PPM? I use Blue Gold's Carb and Hydro for nutrient and did the exact amount they recommend @ 1ml Hydro per gallon of water and 2ml Carb per gallon which raised me to 220ppm (35/40 gallon reservoir) - using a 4x4 Ebb & Flow. Cheers! Love your channel.

[@epicgardening]

That seems low no matter what conversion factor you are using, To raise PPM organically, you basically have to go with an organic certified hydroponic nutrient. FloraNova from General Hydroponics is a decent option there. Thanks for the kind words!

[@willfullyinformed]

Hey I thought you might like to know about this as I emailed the company directly and got a response (below) - maybe this will expand your knowledge? Or maybe you already know of it :) let me know if you have any thoughts or knowledge on this from your experiences, very curious. If I understand this response correctly I'll probably get a veg nutrient so I don't feel the need to foliar my plants constantly. I'm not too happy with reading that they recommend another product to purchase when that wasn't the case in their explanation to buy the previous products (Carb & Hydro). From Eden Solutions: "600 to 1200 PPM/EC is for chemical grows; the Blue Gold works differently from the chems; it shows a lower PPM because the particle size is sub nano and the equipment will not see the charge between the ion exchange. 220PPM - this PPM will work if you foliar feed the top of the plants with 10-15 m/l of the hydro and 5-8 m/l of the Blue Hydro Super Carb. If you really want to push the plants along use the Blue Gold Fusion Compost on the bottom of the plants by mixing 580 to 600 PPM in the reservoir of just the Fusion Compost and foliar the tops with the above recipe. This will bang the plants and production amazing well."

[@bhavinladhad]

Effluent treatment plant for edible refined oils

[@yanyan8289]

Do we need to do calibration when we get a new one? It says it is already been calibrated by the factory and can use it directly.

[@JhunDumsTVXj]

Wow amazing

[@olivierlevesque5596]

Sorry about my last comment just realised that you actually used tap water. Good job.

[@annonvibe5521]

This is a wonderful video, BUT can you please take the background music out? it isn't bad its just extremely distracting for someone even slightly easily distracted. The yell sounds throw off my attention something horrible. Love the video, can you release one without the music. Thank you :)

[@andrewj2411]

Hello. I agree. Great video, but I'm only 8 minutes in, and the music is too distracting. I'll mute the sound and read the subtitles.

[@trishdavi7049]

Couldn't agree more! Could have learned much from this video bit the background noise doesn't stop. Can't watch it all too irritating

[@tahalea]

@@andrewj2411 to pp

[@coreywright6192]

Agreed, I second that motion

[@alexanderhoward6654]

At least use an instrumental track instead of one with a pitched up vocal sample. It's simple. If you're going to be speaking, don't use background music with voices.

[@joyyce03]

Awesome video - very educational and well explained. So what is the best PH, TDS, etc for indoor plants?

[@johnronel7980]

What is the EC reading I should use for hydroponic lettuce?