Local fish tank gurus, I need help!

can you just get a new piece of glass cut for the bottom and seal the sides with edges with a waterproof cocking/sealant? ive made little frog tanks and lizard cages and its not too expensive to get a piece cut to size. like 10 or 15 bucks

my tank is 4 feet long and 18" high, the glass needs to be at least 3/8ths of an inch thick. As I said earlier paying for the glass to be cut isn't the problem, paying for the glass itself is.


The hard part is removing the old glass from the frame, the stuff that is holding it in is similar to asphalt tar, but its rock hard. I'm really not looking forward to taking the whole thing apart... but it looks like that is what I'm going to have to do. Someone suggested using resin to coat the whole bottom of the tank in a thin layer, I think that will be my next attempt at sealing it up. I only worry though that afterwards if it doesnt work and I do decide to take the whole thing apart it will be nearly impossible with the resin in it.


I have almost a full tube of some super duper aircraft stuff that I can just about guarantee will not leak if installed properly. You are welcome to it. (no it's not pro-seal)

it needs to be 100% pure silicone, any other chemicals in it will leech out over time and kill the fish. there are plenty of great waterproof sealers, but not many of them are suitable for aquarium use. think potable water tanks, it has to be something that won't be harmful for drinking water.

what are the dims of the glass you need? i built a coulple tanks and sumps for my saltwater buddies and have some glass in the garage you could have if you need it, just far away?

the bottom of the tank is 11.5x48 or so. wouldn't know an exact measurement until I get the thing apart. And I couldn't tell you from looking at it if the bottom glass is under the side panels or not :dunno:
 
Last edited:
the 'black tar' like stuff is called mastic. and yes, a hair drier will soften it up.

vulkem is low-buck, stuff, nasty to work with... just plain nasty. you're talking 1 tube, splurge on good silicone =)

i'd seal it with silicone, good silicone, not the GE crap they sell at the depot.

im a glazier for a living, hit me up if you have any questions.
 
the 'black tar' like stuff is called mastic. and yes, a hair drier will soften it up.

vulkem is low-buck, stuff, nasty to work with... just plain nasty. you're talking 1 tube, splurge on good silicone =)

i'd seal it with silicone, good silicone, not the GE crap they sell at the depot.

im a glazier for a living, hit me up if you have any questions.

It took 1 tube just to seal the corners of the tank, I don't thing you guys realize how big this thing is. if I reseal it its going to take a hell of a lot more than one tube.. the metal framing protrudes an inch or so around the corners, and would need to be completely filled in order to support the glass correctly.

GE Silicone I is approved for aquarium use, as is DOW #795.. but the DOW stuff is like 9$ a tube. Any mildew-resistant or other silicone with additional additives will kill anything I put in the tank, I don't care how good at sealing up anything it is. No good to me if it makes the tank uninhabitable for fish.
 
Any color would work for me at this point, but again I can't afford the sealant either lol. 795 is what the big tank builders use to seal giant acrylic tanks (like the ones at public aquariums).

email said:
Thank you for contacting Dow Corning. Dow Corning does not market an aquarium sealant. However, a product is available through DAP (www.dap.com) called DAP® Aquarium Sealant.

In the United States, Dow Corning silicone sealants such as 795 do get used for some large aquarium applications ....but.... Dow Corning U.S. has chosen not to market or warranty an aquarium sealant for large aquariums because of the liability if an aquarium should break as water damage can be expensive. Disney and some other customers have chosen to use Dow Corning 795 for some of their aquariums but they are aware of our position and have accepted the liability and they do their own testing and use primers when appropriate. 795 is used in large aquarium type pools around the world with great success, we do 'not' warrant these immersed applications however ...but....people continue to use 795 in these applications because it is a proven performer … quite simply “it works!” but there is no warranty.


Please be advised to test your application since the use of Dow Corning Silicone adhesives in an aquarium application in the U.S. is not warranted.



Sincerely,




Chris Gronski
Dow Corning Corporation - Midland, MI 48686

I wish there was something I could do to patch it, but its looking like I'm screwed. The more I read on aquarium forums and the like the more I see that the inner silicone is just a secondary seal, what really keeps the thing watertight is the sealant between the panels themselves, where glass meets glass. Once that seal is compromised, anything you do to repair an inner seal is just a temporary fix :( so sayeth the aquarium gods anyway. I'm thinking about just laying down a fat layer of silicone all across the bottom of the tank and letting it cure for a few days, that way I don't have to worry about it sticking to anything but the glass and itself. The bottom of the tank won't be visible anyway once the gravel is in. If I do it this way, if I do decide to tear the tank down completely I'll be able to peel it off, versus filling the bottom in with resin or epoxy which would be permanent.
 
Last edited:
if you're gonna give it another try, i can flow you some caulk, ive got a bunch of cartridges laying around (ive got 2 sausages of 795 grey, but you'd need a sausage gun. and mines in the box at werk).
 
I have repaired a 75 gallon tank using marine resin. The tank actually had a hole in it where a rock fell and broke it out maybe the size of a half dollar ish. I mixed the resin with some natural sand and then filled it about a 1/4 of an inch or so. The tank is currently sitting in my mothers house filled with african cichlids 5 years later. Granted like you said it WILL not come out but it wont leak either. I would run a FAT bead of silicone along the edges of the bottom let that cure and then add the resin.

If you dont want to tear the thing down (meaning taking all the glass out right), your out of luck might as well as turn it into a snake cage or planter with some frogs or something. I also think putting all that silicone will only be a waste of money, But it might be worth giving it a try.
 
I have repaired a 75 gallon tank using marine resin. The tank actually had a hole in it where a rock fell and broke it out maybe the size of a half dollar ish. I mixed the resin with some natural sand and then filled it about a 1/4 of an inch or so. The tank is currently sitting in my mothers house filled with african cichlids 5 years later. Granted like you said it WILL not come out but it wont leak either. I would run a FAT bead of silicone along the edges of the bottom let that cure and then add the resin.

If you dont want to tear the thing down (meaning taking all the glass out right), your out of luck might as well as turn it into a snake cage or planter with some frogs or something. I also think putting all that silicone will only be a waste of money, But it might be worth giving it a try.

Thanks for the advice, kind of along the lines of what I was thinking as well. I used it as a snake cage for 6 years until my snake got over 7 feet and I figured it was cruel keeping him in there. That and the wife was afraid it was going to eat my daughter when she was born :D

I think I'll tear it down and put it back together right. here comes a big ass project I wasn't ready for lol.
 
if you're gonna give it another try, i can flow you some caulk, ive got a bunch of cartridges laying around (ive got 2 sausages of 795 grey, but you'd need a sausage gun. and mines in the box at werk).

that may just be the dirtiest sounding thing anyone has ever said to me :gee:


May come in handy when putting the thing back together to fill the side panels. I'll get ahold of you once I get it all torn down and see what I'm up against.


Thanks for the replies and advice everyone. I would just junk it but man this old SOB is built like a tank, and I love the utilitarian look of it. Almost looks like it belongs in a sci-fi movie full of eels and human parts lol.
 
the 'black tar' like stuff is called mastic. and yes, a hair drier will soften it up.

vulkem is low-buck, stuff, nasty to work with... just plain nasty. you're talking 1 tube, splurge on good silicone =)

i'd seal it with silicone, good silicone, not the GE crap they sell at the depot.

im a glazier for a living, hit me up if you have any questions.

Vulkem 116 is about $9.00 a tube. Cheap? It IS Nasty as Hell and will not leak if applied correctly. But Mike, I do not think Vulkem if safe for any living thing. If that corning is the same price and safe, sounds like the stuff.
 
chances are you have raw scars older then me, so sorry if im spreading bad info.
i dont actually buy the stuff, so i only know what im told. i know my company has used vulkum in the past to save money, but we use 795 for everything we care about being waterproof, with the exception of 799 for clear or aluminum for panels.
 
I worked for Aluminum Skylight in Sante Fe Springs back in the early 80's. It was all we used to glaze the lights before Perm stops. :banghead:I hated the stuff, I think I still have vulkem on Me somewhere. lol
 
that was clean by glazier standards, we make caulk jokes professionally.
the sausage part was refering to these suckers.
http://www.sealantengineering.com/i//tn_DSC04071_1.JPG

ive wanted to re-seal an aquarium sinse i got started doing this a couple years back, you're hide's the caulk joint, but i could do beautiful caulk joints anyway.

I definately will give you a call when it comes time to seal it up. I epoxied the cracked panel from the bottom tonight just so the glass wouldn't fall apart too bad when I take it apart, I think I'll start trying to carefully get it apart tomorrow morning.

Oh well, gotta love a good project.

this is all I could think of when you said sausage gun though
beefcase.jpg


:gee:
 
Dude sucks that its busted why are you not wearing at least filp flops working with glass?

I took it apart in a different part of the garage, and was wearing full shoes while working on it. i moved it over there on the pieces of foamcore board that its sitting on. its too damn hot in my garage i took the shoes off to start scraping the tar crap out of the tank frame ;)

thanks for the concern :gee:
 
I took it apart in a different part of the garage, and was wearing full shoes while working on it. i moved it over there on the pieces of foamcore board that its sitting on. its too damn hot in my garage i took the shoes off to start scraping the tar crap out of the tank frame ;)

thanks for the concern :gee:
Aaaahhahsmiliecopy.gif
 
lol it was 88 outside and 112 inside. the damn door to the garage faces west so i get full sun from 3pm on till about 7. the flat roof that is nothing but tar over 1x6 slats ensures that it gets nice and sweltering in there by 10am or so.


got the bottom of the tank scraped clean of all the tar crap. its actually still pliable where the air hadnt got to it, so im pretty sure the rest of the tank sill still seal up, the sealant was only dried out around where the cracks were. im hoping I can get away with only redoing the bottom, i don't want to risk breaking the sides like the bottom did.

here's what it looks like right now, back to work tomorrow morning.

41339_1477343267228_1643138606_1175345_4346578_n.jpg
 
I have glass cup's...Just sayin. I wonder if it is mastic, mastic is pretty nasty in it self. Bathrooms we used white mastic, not sure if they are different chemically. I think I would use the 795 You and XCM were talking about. And if You can get Him to come out and lay some calk for You. NO ONE uses their caulk like a Glazier. :)
 
Back
Top