Silicone on Acrylic - Which ones actually stick? DIY aquarium windows

Today I'm looking at one of the most common question I see anywhere: Does silicone really not stick to acrylic? Which kind should I get to make a baffle or sump?
I applied ten different silicones to a test sheet (a few days after removing the protective cover to let micro-scratches build up) and see how they hold up to being pulled at and gouged.
The end result? Three which will almost certainly work for anything you're doing, one which is good enough, and a whole bunch of garbage from GE that doesn't work AT ALL.
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[@Seanmmvi]

Not all heros wear capes. thank you for doing this! I know this was probably well over $200 in silicone

[@Aesklauen]

bruh, I've been recently on acrylic related projects and includes terrariums and aquariums. this helps a lot for the correct sealant. thanks a bunch.

[@GG-ec5eg]

probably one of the most strait to the point informative on everyday real life products pro's and con's video youtube has, thanks man your what many others need to look up to and take notes on these type of videos.

[@weezy84454]

Love this guy's honesty

[@davechamberstube]

Thanks for doing this. I was amazed when my high quality dow silicone peeled straight off my acrylic! Most of those products aren't available in the UK, but the Gorilla is! you've saved me a lot of heartache!

[@peepiepo]

Is that the Dow 785 ? I'm struggling to seal my acrylic shower tray that seems to be particularly difficult and was thinking about trying Dow as I've seen lots of people recommending it.

[@jonmurph589]

Very helpful video. Thanks!

[@riskyraccoon]

appreciate you taking the time to test these

[@elainebenes5932]

Working on a crafts project sealing seashells to acrylic sheets. This video was so helpful! Thank you so much for the work you put into this.

[@patrickmertz2426]

Great informative video, thanks for your troubles in making and posting it. Cheers from down under.

[@mermaid3152]

Wow! Exactly what I needed to see. Thank you so much for the info!

[@laralynnenabozny1822]

Very informative. Thank you!!!

[@jamesallen6007]

Many thanks for taking your time, and own money, in doing this very informative video. You have earned my subscription.

[@jd4810]

Thank you very much for this informative video. Your video has been so helpful for completing my projects.

[@kimberlytillson2457]

Thank you!! You saved me time and money!!!

[@markstevenson195]

thanks! For plexi prep after sanding, maybe try the pvc pipe solvent ( not glue) . it comes purple, but you can get it clear. It etches PVC plastic for glue bonding..

[@alaashaghouri9763]

your video helped me a lot, Thank you very much for your great content

[@dreamelyte]

Thank you so much for this helpful video. I'm definitely sure you have saved so many people's time, money, and energy!!

[@lorenjanwilson]

you are a genius and this video is awesome!

[@thesilkkradle9558]

this was good mate thanks

[@michelhaineault6654]

This is the best test Merci

[@fugitivetattoo]

Awesome vid

[@DaveDazeBeats]

Thank you for this

[@athrunzala5337]

thanks good job !!

[@Shananana99]

Very helpful thanks!!

[@inhaleingsmoke]

Very good sir

[@nickmiller9677]

Thank you! I had a ikea display convert terrarium constantly leaking ! I was doing everything to make it work when I finally realized it was the glue !

[@jonathanlevin7660]

Wanted an acrylic adhesive safe for drinking water, but strong enough to hold it together. Will order the DAP. Thanks!

[@Z-Ack]

If bonding acrylic to acrylic then you want to get the special stuff that physically bonds the two together with a solvent.. its real watery compared to any sealant but if you hava a flat piece set flush and square to another piece you run a little down it and will get sucked into the seam and join the two pieces where if you try to break them apart it will break at another place and not the joint:..

[@ElGalIo2]

Downsil 732 amazed me!!! 275 pound electric motor hanging on just with a bead... Had to actually use a Steel Chisel wedged in between the steel faces just to get the motor apart. Electric motor was hanging on by Chain Fall.

[@yvettereynolds5945]

Thank you

[@user-vc5rp7nf8f]

thanks. looking to glue some acrylic together. great info

[@MischiefandFins]

I wouldn't use any silicone for an acrylic on acrylic bond, the ones that stick work ok to stick acrylic to something else, but it's not a great solution. Acrylic on acrylic I'd see if the joints are close enough to use an acrylic cement, and if not I'd try a rubber sealant like Lexel, which has a much better bond to acrylic than any silicone will

[@user-vc5rp7nf8f]

@@MischiefandFins thanks. yeah there's a part of the project with tight joints so i'll be looking into something like Sci grip 16 or E6000, or maybe super glue. Then there's some other fittings that will go onto the acrylic box which may not be super flush, so i'll need some larger 'filler' adhesive to get all the gaps etc. i'll look into lexel

[@casual257]

what glue to use on plexiglass to glass, i am in the need to plug aquarium drilled hole in the bottom glass, i was going to use ge1 , but am confused

[@regimengonzalez8667]

What would you recommend for a non leaking crack in acrylic

[@aaronstestlab]

Great vid man! Out of curiosity, have you ever considered a polyurethane adhesive?

[@MischiefandFins]

I might trust something like 3M 5200, with a coating of silicone over it to keep the zinc from leeching out, but I haven't had much reason to test it, and if I'm coating things with silicone to make them aquarium safe it feels easier to just skip to the silicone and hope. I may try some experiments with PL Premium 3x and the like when I have some spare plywood and time.

[@bluemarbel1242]

Thanks for taking the time to create such an informative video. I want to caulk my house windows from the outside (not aquariums). Are your durability tests still relevant? Would you still choose Gorilla Silicone Sealant over GE II Silicone when using it on exterior windows in cold climates? TIA

[@MischiefandFins]

If your house windows are acrylic I would really recommend a product like lexel instead. The reason I didn't suggest it in this video is that it is too flexible to hold up to water pressure, but that flex is a benefit for standing up to wind flex and different expansion rates as things heat and cool. It's a really solid product for everything other than fish tanks.

[@plywoodgyaan1305]

Thanks for your video.Sir, please guide me which silicone is best to stick glass to plastic or fibre in wet area for gaad bonding

[@hkirk23]

Hey man quick question. I’m installing an acrylic window on a plywood tank. Which of these would you use as gasket between the acrylic and the wood that has a epoxy resin?

[@MischiefandFins]

smaller plywood tanks i usually use gorilla silicone, larger tanks i order momentive rtv 108 from amazon amzn.to/39T9Qwb the momentive is far better than the stuff in this video in pretty much every way, this was just testing stuff i could get at local shops, but i've used the gorilla silicone in several tanks and been happy with it years later. after installing the windows you want to be sure to apply a second sealing layer around the outside making good contact with the cut edges of the acrylic, it sticks very well to the cut edges and that keeps the front seal dry, which makes sure that it will hold well long term.

[@ChrisLocke1969]

Great video, thanks for taking the time and money! But I'm puzzled by two things... if they are all 100% silicone, A) how can they be different strengths? B) how can they be colored?

[@MischiefandFins]

"Silicone" is a mixture of different lengths of siloxane molecules (alternating silicon and oxygen atoms in a long string). The properties of the mixture are changed both by the length of the molecules, the mixture of different lengths, and where and when they have hydroxide or hydrogen groups attached. This is why any given company might have 14 different kinds of silicone under the same brand, since some mixtures are great adhesives, some are great sealants, and some are great lubricants. It's more a generic term for a class of molecules than a particular product, and that's why you can buy silicone grease, oil, adhesive, sealant, resin, etc. The second question, they're generally between 1-3% colorant, carbon black, titanium dioxide, things like that, and the claim of "100% silicone" is just a marketing term which is entirely meaningless

[@Z-Ack]

That was by far the most intelligent and best possible answer to a commenters question i have seen... like so much so it made me think and realize such.. good shit.. shoulda been mentioned in the video which woulda given a bit more merit to your overall experiment to the doubters..

[@sasquatchdonut2674]

Which one would you recommend to bind acrylic to glass?

[@mohamedussama7595]

What is the best for bonding acrylic logo to glass ????

[@stripclubpsychology]

Is the Gorilla sealant or others you recommend SAFE for the fish and won't harm them?

[@gueto70]

Caulked my 120 gallon turtle tank with GE silicone. 30 minutes later one of the turtles pulled the silicone out of the corner seam creating a water feature in my living room. Found gorilla silicone in stock at Minards so I have my weekend planed. Thank you!

[@MischiefandFins]

Just be sure to give it an extra day to cure vs what you would do for normal silicone, for animal safety. It has more volatile additives than other brands. I don't really worry about it cause my projects are usually weeks between sealing and final fill, but being in a hurry with gorilla brand is more dangerous than with others, so best to play it safe

[@Chanmantroop10]

Did the gorilla silicone work and hold up? Going to need to redo my acrylic tub surround in the future as I noticed the areas attached to the tub peeling vs the area on the tiles that are stuck on like glue

[@gueto70]

@@Chanmantroop10 The gorilla did bond well but it has no flex. With the temperature shifts and minor movements between the tub and panels it needs to give a little. That is why silicone will eventually come free from one side. It's the week link that gives rather than the surround cracking. I drained and cleaned the tank several months later with warm water and the acrylic cracked. Don't know if it was the lack of flex or just 20 year old tank but new one has GE silicone again and holding fine. Clean the seams with bleach and scotch bright pad before you caulk to get a good bond.

[@Chanmantroop10]

@@gueto70 I didn't want to scuff my tub surround but might end up having to. Better than having to redo often vs once every few years

[@gueto70]

@@Chanmantroop10 use the blue scotch bright for glass. Micro scuffs you can not see. Key is get it completely clean and dry first then let it completely cure. 24 hours is the minimum time. Acrylic tubs and acrylic glass are not the same. Property management and contracting for 40 years. Just use GE silicone on tubs.

[@bimalmitra99]

Tell me what silicon is best for 7 fit 12 mm glass aquarium

[@MrAlienautopsy]

Enjoyed your very informative video but I have a nagging question. When I went to pick up a tube of the Gorilla clear sealant it shows in the fine print that it's not for underwater or aquarium use. So is the key just the adequate curing time????

[@MischiefandFins]

The only silicones that don't say that are the ones that are marked specifically as "aquarium silicone" It's just a liability thing, they haven't done any official testing for food safety or anything so they have to tell people not to use it for those things. "Aquarium silicone" uses the same toxic curing agents, and will also kill fish if not cured completely. The big difference from one kind of silicone I to another is just the length and shape of the various siloxanes used. I assume longer straighter chains make better adhesive, and curlier more tangled chains make better sealants (just a guess based on pretty limited organic chemistry knowledge), but it shouldn't matter for aquarium safety, as they really only leech out at very high temperatures in oil. The big difference between gorilla sealant and, say, dap aquarium, is that gorilla appears to have added a small amount of benzene, because benzene helps siloxanes to straighten out. This additive is likely the reason for the significantly better bond, and it is arguably a carcinogen, but it should be essentially entirely bound up in creating longer siloxane chains as it cures, unless, again, it ends up getting hit with very hot oil. So I give it a couple extra days of degassing to be sure, but it evaporates very fast, so the cured product shouldn't be any better or worse than any other on the market. Definitely more toxic before curing, though.

[@dennisburd8252]

@@MischiefandFins So gorilla has a cure for cancer. ha

[@giovannivild7922]

This is informative. Thanks.. do you think that if prepped right I could use that to reseal a leaking seam on a 300 gallon acrylic? And would you happen to know anything about weld on products and what the process would be to seal with that thanks a lot

[@MischiefandFins]

Really a bad idea to use silicone for anything other than installing windows into tanks made of plywood, concrete, or metal, I'd definitely use an acrylic weld product first, if the tank is in good condition and the seam is still flush I'd go for a water thin product like weld on 4 and see how it does Personally I'd try that first, and if it didn't work or if I just felt like it didn't bond cleanly enough for comfort then I'd use a little bit of lexel, which is a clear liquid rubber. It sticks very well to acrylic, but it takes about a week to cure completely when applied even in a very thin bead

[@giovannivild7922]

@@MischiefandFins thanks. I appreciate it. I'll try wheeldon

[@dcurtis5027]

Also try Permatex Silicon RTV adhesive sealant, 81158, black or clear. It works very well on acrylic.

[@0dirty]

As these silicones go, which ones are reef, or aquarium safe? The Gorilla silicone looks to have an anti-microbial component to it, which would be toxic in a reefing application.

[@dirtbikesnfishing]

So will this be good to bond acrylic to wood for plywood tank 😊

[@RexDogDelivers]

TY for the video. I have a bunch of holes in Glass tanks to patch. I have Lexan patches and I hate the brown crap I have been using. I have been patching from the back. It holds but dam it is Ugly. I will patch from the inside with clear gorilla the the rest of the tanks.

[@MischiefandFins]

That's how I do it with old plumbing holes, haven't had any idea after several years. Lexel also works really well for that if your holes are near the top, it's crystal clear so the patches are a lot less visible. Only real down side is it takes about a week to fully cure.

[@RexDogDelivers]

@@MischiefandFins a week?! OK I am warned. Yea these are old Walmart tanks so top and bottom of the backs. I figure patch from the inside (others are patched from the outside). We have so many tank the time delay will be fine. I think there is 5 tanks left to patch. We started the room with perfect measurements and some how the contractor messed up the first wall (may have been my fault) and since that was off I just completed the room with the new size and had to do a wall of 30 longs ( 3 sections each) and then since there were so many we did a center spine with them also.

[@rabidrabbitsmokingneonlights]

What did you do with all that unused silicone

[@frikfrak5286]

I'm trying to fix up a 5gallon little plastic tank. Think of welding the plastic first and then using the gorilla snot after

[@ocrun6765]

I need to seal a custom joint in a shower. Will the Gorilla hold up well with hot (shower temp) water?

[@ivonnetjioe9370]

Hi, a question, but is it possible to stick the acrylics to a silicone rubber sheet? with the silicone glue?

[@MischiefandFins]

Silicone doesn't really stick to rubbers, and does a pretty bad job of sticking to other silicone products. I'd be more likely to try a liquid rubber sealant like Lexel for that, but things really just don't stick well to silicone rubber in general, so that might not work either

[@LandyAndy62]

Lightly scuff the acrylic surface with 220 grit, apply a thin coat of MEK (Methyl Ethyl Ketone), let it dry and then bond it with any good quality silicone. This works because the solvent breaks the polymers in the surface of the acrylic and fluffs them up giving the silicone something to grab onto. MEK is nasty stuff - don’t get in on your skin or breathe the fumes! and don’t use too much or it will destroy the structural integrity of the acrylic.

[@mealticketraceway]

Lol love it. Lol good job. And I will try it o what about flex seal. If you tryied it send me the link

[@r9p0m7p8]

Did you forget to turn off the water, or someone's taking a shower? :). Thank you for the silicon reviews; we're about to place in our building acrylic based sign on the building and wanted to see what silicon to use for that brick. Thank you for the scratching tip; it will help a lot. :)

[@darkmode867]

With the amount of water damage that can happen from an aquarium ill still to aquarium silicone. There is a reason its rated for the purpose. But helpful to know for other projects.

[@willparsons32]

Great video! Well informed however, as the rule goes; if it specifies that it contains a anti-mold/fungus ingredient, simply leave it on the hardware shop shelf!! Why stress when there's Lots of others that are Aquarium safe!?!

[@tidalboxer]

I’m wondering if this will work for a project I’m working on. I do spfx and costume stuff. I had some acrylic pieces I need to stick an already existing silicone piece. It’s a silicone creature glove with acrylic claws. I’d used a Swiss superglue type thing meant for these two, but the bond just isn’t strong enough. I wonder if the gorilla glue would work. Looks fantastic.

[@azza2664]

Hi, I'm in a similar situation to you needing to bond acrylic to silicone mould. Can I ask if you found anything that works well? Thanks

[@tidalboxer]

@@azza2664 well… ya know I just thought I’d test it with the silicone I use for patching and adding pieces and paining by mixing in color. I think is what all the big mask companies use for all that. It’s 732 Dow Silicone. I have acrylic claws needing to attach to silicone fingers for a werewolf glove. I just used the 732 since I never tested it and thought I should try. Everyone and all things I looked up said it doesn’t stick. But this did. It worked just fine and it seems stronger than any specialty glue I’ve found to use for this situation. I say watch this guy’s video and get the best sticking power silicone… which seems to be the gorilla. I think it’s working fine with my 732 as well. I bought some weird Eastern European “superglue” last time they fell off and when I went to go try to glue the claws again it was dried out. So… not worth it. Just test some pieces with silicones suggested here or the 732.

[@tidalboxer]

@@azza2664 ok. So after replying, I just went back and looked at the acrylic claws attached to the silicone gloves. The silicone attaching it DOES seem to be disintegrating and breaking down some over time possibly. There’s ones I used more on that seem to be ok, but there’s a couple that look like they’re ready to come off. And the silicone adhering them is stating to look a little dried out and flaky. I’m assuming it’s probably a slow chemical reaction between the two substances. I used 732 Dow and not anything he mentioned in this video. After watching I think I still want to try some of the ones he mentioned like Gorilla as they are talked about adhering acrylic well to glass via the silicone as glue. If he doesn’t get a chemical degradation with some of the better silicones as glues, I’d think it’d be ok for us to use similarly. Either way, nothing I’ve found so far is working 100%. Even the Swiss superglue meant for it seemed to only stick very lightly and come off with and hard pull. If the silicone sticks better, but degrades slowly over time… I feel like it’s still a better option than the Swedish superglue. With that it doesn’t stick well. I want to let them sit for a while and then see what happens and I’d like to experiment with his other silicones if this fails.

[@azza2664]

@tidalboxer thanks a lot for taking the time to reply. It's good to know that even the Dow 732 is forming a bond and maybe some of the products listed in this vid might do better. I'll be able to test it out myself too in the not too distant future so if I find anything that performs well I'll let you know 👍

[@tidalboxer]

@@azza2664 yes. Please do re comment here to let me know what you find. I’ll do the same because it’s a hard question to get answered. And apologies for misspelling or punctuation errors. I text fast and have ADHD, so I miss a lot. I do know the difference between too and two though. Lol

[@brandonbigras7753]

Test everbuild aquarium silicone.!

[@fugitivetattoo]

Great vid!...part of the demonstration was unclear to me; Did the Commercial Kitchen require scuffing? And how did you clean/prep surface? Thank you.

[@MischiefandFins]

I didn't scuff anything, the surface was as smooth and new as possible when doing this specifically to check how well they would bond to the acrylic itself. Any scratches showing in the video were on the back side. Painters tape to block off an area followed by light sanding is absolutely recommended for surface prep

[@fugitivetattoo]

@@MischiefandFins nice. And I was asking if you needed to clean the surface. I thought maybe the sanding debris needed to be wiped down with alcohol maybe Or mild soap before applying the sealant. Thanks

[@MischiefandFins]

@@fugitivetattoo no, I just blow away any dust, wipe it off with a clean shop rag to pick up any dust that's sticking from the static created, then apply silicone. There aren't any protective layers or oils or anything applied to the sheets in the factory that need to be removed, just the anti scratch plastic to be removed, scuff it a bit, and you're good to go. I often don't even bother with sanding, though, the cut edges are usually rough enough to stick exceptionally well, so I add enough to the front to hold it in place temporarily then use a very large bead around the edges for the actual water seal/hold layer, that way I don't have to worry so much about getting the alignment perfect to hide the sanding. That's using much better silicones, like momentive rtv108, though. I do always sand when using any of these, even if it's a pretty thin area.

[@fugitivetattoo]

@@MischiefandFins done deal man thank you very much! Thanks for the time and money you spent, the info in this video is like gold to a DIY'er!

[@JK360noscope]

$6 each... Very nostalgic when I go to Lowe's now. $$$one million billion dollars please!

[@hzuiel]

Based on my research the key to bonding acrylic with silicone is surface prep, there's some rather nasty chemical that a swab of on the acrylic will make silicone stick like none other. methyl something or other. I'm trying to look it back up again now. I personally would not trust any construction silicone because they aren't required to say what's in it or grade it's safety since that is not it's intended purpose, and most of them that say how long it lasts and that it fights mildew, have chemicals in them that constantly leech out, to fend off mold, mildew, fungus, whatever. You can use 100% pure aquarium silicon and pre-treat the acrylic and use rubbing alcohol on the glass and it should bond strong as hell.

[@MischiefandFins]

The idea that silicone products have mold inhibitors that are killing your fish or corals comes from the fact that people don't understand the difference between silicone I (acetic acid cure) and silicone II (ammonia cure) add water to tanks with Silicone II before it has cured, causing their fish to die. People don't understand it, so they assume it's some mold inhibitor, and that's just the "common knowledge" now, despite it being wrong. Great example, everyone has been obsessing about buying GE Silicone I for windows and doors for years because it "doesn't have the additives" well it says "7 years mold free protection" on it now, but the formula didn't actually change, according to the GE person I talked to, but since nobody actually knows a damn thing about how any of this works they're all freaking out over it, when it's the same thing it's always been and they just added marketing to the package. Now people are chiming in with "I used GE silicone 1 once a long time ago and it killed my corals!" because now suddenly it must have had it all along, right? No, it's a garbage product that sometimes doesn't cure correctly, people just don't know how to actually check that. Uncured silicone is full of toxic stuff. Silicone is naturally mold resistant. It is a 100% synthetic product that resists cracking, so with regular cleaning a silicone with no additives will still have a 7 to 10 year "mold free protection" There certainly are silicones with mold inhibitors in them, like "PENOSIL no mould" or "Forever Clear" which make a big deal about the special additives, there are special versions of GE Silicone II with "lifetime mold free guarantees" which clearly have additives, but... otherwise it really isn't an issue. You just need to know to let stuff sit for a week to cure, people are too impatient and add things after 24-48 hours, and then go looking for someone else to blame when things go wrong.

[@tidalboxer]

We’re we’re taking in a post above about similar things and trying to figure out if any bonding substance would adhere acrylic to silicone. I’m trying to glue acrylic pieces to a silicone object basically. It’s a realistic silicone glove for a special effects creature/werewolf and I need to glue one acrylic claw to each finger. In the beginning I used a European glue made for specifically gluing acrylic to silicone. It barely stuck and the acrylic pieces pulled off easy. The substance was more of a superglue looking substance with a cleaner vial of liquid included to clean the surfaces you’re gluing before adhering the glue. I think it was pretty much superglue and acetone for cleaning the surfaces. When the claws finally gave and pulled off, I went to use the “superglue” again and the substance had dried out completely in the applicator tube. It behaved exactly as superglue would when it dries out after you open it. So with it’s looks and behavior, on the glove and in the bottle drying out, I think it was a very similar substance to superglue. So about a months ago I tried 732 Dow Corning silicone that is used by prop makers to repair silicone, glue silicone to silicone, and to color and thin out as a paint for smaller projects. 732 silicone worked great at first, but I waited and just looked now. The claws I used a bigger amount of the silicone “glue” on seem to still be sticking ok. There’s a couple of pieces I glued on with a lighter amount that might be reacting though. It seems to be drying out and turning flaky and cracked. Not 100% sure it’s a reaction, but not sure it isn’t. I’ll probably have to wait longer and reassess. If it doesn’t stick, my next step it to try some of the silicones in this video. Maybe the ones recommended will be stronger and not react? Any suggestion before I try a next step though??

[@manjurmahammadmomin3897]

How to bonding ss to acrylic

[@MachuPichuu]

It would be good to mention that Gorilla Silicone is labeled as not for Underwater or Aquarium use. It also has algaecide and the MSDS lists it as having numerous chemicals that are harmful to aquatic life.

[@MischiefandFins]

Nearly every silicone, including those used by aquarium manufacturing companies, says that their products are not for underwater or aquarium use. It's a liability thing. For instance, SCS1200, which is very commonly used by high end tank builders, says not to use it underwater. GE Silicone for plastics contains chemicals that cause liver failure, cancer, and reproductive issues. The takeaway of the SDS on silicone is that you can't put uncured silicone in an aquarium. For instance, the MSDS lists "acetic acid" as aquarium acute toxicity. Vinegar. Yes, vinegar should not be dumped into your aquarium, but it also evaporates as the silicone cures. "Silicones" are chains of siloxanes, chemicals like benzene are incredibly dangerous in uncured silicone, but become part of the long chains while curing, altering the end structure, creating longer straighter chains or twistier more tangled chains. The benzene is the reason that gorilla silicone sticks better than the others, but it becomes linked in the actual siloxane chains as it cures, with the excess off-gassing. To release it would generally require heating the silicone to several hundred degrees in oil, basically frying it. Of course, this means it can't be considered "food safe" in a kitchen where it may come into contact with things like pans or hot oil. The "algaecide" thing is largely just people on forums misunderstanding why silicone II sometimes kills fish and sometimes doesn't, and misunderstanding when things say "mildew and mold resistant" as a comparison to acrylic caulking which will end up with mold and mildew penetration due to cracking due to the fact that acrylic caulk expands and contracts with temperature and silicone generally does not. Given proper curing time there isn't really anything in it that I consider to be an issue, especially with regular water changes being done, and it is as a cured product generally safer to be in your fish tank than Tetramin fish food.

[@rohankumar3793]

which is best silicon for acrylic to acrylic

[@MischiefandFins]

acrylic to acrylic you should really use an acrylic cement. Even a really high end silicone like RTV108 or SCS1200 will only really make a gasket seal on acrylic long term. If you're making an acrylic tank, use acrylic cement. If you're trying to do something like fix baffles into a sump, something like Lexel works far far better than silcone on acrylic, but it takes 1-2 weeks to fully cure. Lexel is covered in "no aquarium" warnings, but several bigger pond companies use it to install drains and things, since it sticks to rubber liners better than silicone, and they haven't had any issues. Just don't use to to try to build a tank, it's far too flexible to hold a tank together.

[@rohankumar3793]

Angelfish Unlimited ...thank u so much sir

[@countsd1]

Weld-on 4 and Weld-on 16

[@omkarahi]

Common Nail Polish Remover is the cheapest and strongest glue to join Acrylic sheets. But it must be Acetone based.

[@paulb8188]

NO LONGER AVAILABLE at Lowes. Amazon has it

[@MischiefandFins]

Yeah, I hate that. This was supposed to be a comparison of the mediocre products available at hardware stores, and everyone around here stopped carrying the good ones. If you're already going to amazon, there's better stuff than what I tested here, Momentive RTV-108 or GE SCS 1200 are WAY better than any of these

[@demonslayer8085]

@mischief and fins Have you tested loctite silicone yet? I need to glue an 1/2” acrylic/plexiglass panel to my aquarium glass and have a tube of it at home. Not sure ho well it will hold especially after watching this vid where you showed that most of these common silicones are garbage!

[@MischiefandFins]

No, if it's not in the video then they don't have it at my local stores, so I wouldn't have had occasion to try it. You might do a search on the monster fish forums to see if anyone has reported anything

[@demonslayer8085]

Mischief and Fins Damn, alright I’ll try to see if there’s any reviews of it. The only other sealant I have at home, which I just bought a few days ago is the GE Silicone 2+, so I guess I may have to order the Gorilla silicone online as my local stores don’t have it 😕

[@MischiefandFins]

@@demonslayer8085 out of curiosity, what are you doing? Is it like... An add-on, or a side repair, or?

[@demonslayer8085]

Mischief and Fins Basically I have a 17 gallon tank that I am trying to divide in half with a 1/2” thick black acrylic/plexiglass sheet so that I can put one male betta fish on each side. I’ve tried cutting the plexiglass as close to the inner length of the tank as possible but will still need to use silicone to hold it in place. My main concern is worrying that it will not stay in place (fall over) after the tank is filled with water, so I really need a strong silicone that will hold/stick to acrylic as well as glass. This is especially important because i plan to leave a 1/8”-1/4” gap from the bottom so that I can just use one heater to heat both sides of the divided tank. I saw another KZbin video where this guy did a review of the GE Silicone 2+ and said it was good so went to buy that before I saw your vid today 🤣

[@MischiefandFins]

@@demonslayer8085 there's probably not too much worry either way with that, honestly. If you run silicone on either side it will stay stuck to the glass, and will probably stick to your cut edges pretty well. If it doesn't need to be water tight it's just less problematic

[@neychelanneparungao3024]

Weer to buy this item

[@aquariumhacksbymarcus5653]

Just one question if I have a leak in my are acrylic aquarium will the gorilla silicone work

[@MischiefandFins]

Leaks around joints? If it's an all acrylic aquarium, try a solvent cement in the leaking joint first. If that doesn't work I'd be more inclined to use lexel for very small leaks, as it sticks to pretty much anything. I've used it in several ponds and tanks with no issues. It will stick much better, but it takes a week or so to cure, even when applied very thinly. If it's a crack or hole I would cement the crack using solvent cement, then cement another sheet of acrylic over it. Silicone is more of a "sticky gasket" on acrylic, really no good for patches in my opinion. I trust gorilla silicone to hold a window against resin. I wouldn't trust it to hold acrylic against acrylic.

[@aquariumhacksbymarcus5653]

@@MischiefandFins thank you for your response it's an all acrylic tank with a small leak on the bottom where they meet up together so what you say weld on 4 and then weld on 16 on top of that

[@MischiefandFins]

@@aquariumhacksbymarcus5653 with that spot, if it was my tank I'd masking tape the outside, weld on 4 the joint, give it time to dry, then lexel the whole bottom seam to be safe, cause I'm paranoid that one leak means bad cement in the whole tank. But that's just cause it would be covered by substrate in any of my tanks anyway

[@scottrobert2724]

acrylic to glass whats best now its 7 yrs later

[@TheRealFreznoBob]

Thx bud, good job.

[@kayrin33]

Unless I'm misunderstanding, the SDS sheet on the gorilla silicone it indicates it is "harmful to aquatic life with long lasting effects". complyplus.grainger.com/grainger/msds.asp?sheetid=4189565#sec10

[@MischiefandFins]

Half of those are in literally every acetic cure silicone on the market. Pretty much everything in any brand of silicone is harmful to aquatic life prior to curing. Unfortunately the SDS of a product is really only useful for understanding the dangers of the product fresh out of the package. The only really questionable thing in gorilla silicone is benzene, which helps to create much longer silicone chains and evaporates incredibly quickly, so there isn't really any of it left after a week of sitting, which I know since it is INCREDIBLY deadly at even microgram doses to aquatic invertebrates, yet my shrimp, crabs, daphnia, etc are all fine and thriving. The other things are deadly if added directly to a tank, yes, but you aren't doing that, and you certainly aren't adding 7 grams of silica dust per liter of water in your tank.

[@kayrin33]

@@MischiefandFins Thank you so much for clarifying. Its is a bit overwhelming to get through all the SDS info and try to make sense of it. Im happy to know I misunderstood, and happier to know that I can use the gorilla glue without harming my fish!

[@MischiefandFins]

​@@kayrin33 I'm working on a "silicone misconceptions" video right now to answer some of these questions a little more thoroughly, because they get asked a lot. I generally let gorilla silicone sit for a few extra days to be certain, but my projects are generally of the "start on it, set it aside, pick it up again two weeks later" variety. My general "safety" rule with any silicone is to wait 4-5 days to be sure there isn't any possibility of anything leeching out. I then do a fill, let it sit for a couple days to leak test, then a full drain before decorating.

[@MachuPichuu]

I appreciate you doing this test but i feel like you were not consistent at all on the bead pattern or thickness. For example the GE silicone for Acrylic had a very smallest bead. I'm surprised that performed so poorly on your test because i have done a similar test with that and it held extremely well. I would say as good as the Gorilla silicone. Most of the other GE silicone do perform very poorly on plastics. As you saw in your test.

[@MischiefandFins]

The stuff didn't stick, several tubes were bad before opening, the QA is just terrible on the product, and if you happened to have an experience that was different it really just highlights the problem of inconsistent quality. My bead size isn't responsible for that. A piss poor product is.

[@MachuPichuu]

@@MischiefandFins I suppose I won't argue that the QA is quite bad. I noticed that usually I can tell on the smaller tubes which one is bad by just squishing the tube. The bad ones tent to be lumpy feeling.

[@countsd1]

FYI, Silicone is not made to stick to acrylic bro. It's made to stick to glass. You are supposed to use a chemical bond like Weld-on 4 and Weld-on 16 to weld acrylic.

[@MischiefandFins]

acrylic cements don't do anything about adhering acrylic to something other than acrylic, which is the point of this. Good luck attaching an acrylic window to epoxy using one of those products. To be clear, lots of people want to add acrylic baffles to sumps, or use acrylic windows in plywood tanks, and there are actually quite a few silicones which work very well in that use case, you just can't use them to make a watertight all acrylic box.

[@countsd1]

@@MischiefandFins You can get a glass aquarium and then have glass panels cut to size and then silicone them in place for a sump. It would be cheaper as acrylic tanks are more expensive. Easier to find a used glass tank too.

[@j2bro15]

Are Weld-on Acrylic cement watertight/waterproof?

[@MachuPichuu]

@@countsd1 Except its much cheaper to get a glass tank and use acrylic panels for sump or overflow. Plus acrylic is much easier to cut at home than glass. That is the point to attach the acrylic to glass.

[@karlmullowney998]

READ THIS : Why don't you hold the tubes steady instead of shaking them around and making them difficult to recognise on the shelves of hardware stores . Thanks

[@MischiefandFins]

How about this. You go spend $150 on supplies and waste a few days making a video that does whatever it is you said here, and send a link when you're done, and I'll tell all my subscribers to go watch your video because you did whatever it was you're complaining about, i don't know, i don't read comments that start with READ THIS out of spite, even when they're short, because you aren't entitled to my time

[@darkcyberdyne]

Asi silicone

[@evankawi4219]

I found the 100% percent silicone gorilla glue at Fred Meyer Fred Meyer is a gorilla glue dealer

[@SilverDemon456]

Very informative, thanks!

[@countsd1]

Sorry to interject. I have had to do this and if you must use silicone on acrylic this video would be very helpful.