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WAbedroomponics
01-11-2012, 04:34 PM
My 40 gallon acrylic cracked at the top it leaks about a rain drop sized amount of water every 10 seconds. I looked all over but can't find good info on how to fix it. does anybody have any tips on fixing it? it is also hazy so I would love help with that to but i should probaly go at this one problem at a time.

foodchain
01-12-2012, 04:19 AM
Haze can be buffed out if it's from scratches. Just a pain to do, and often leaves distortion ripples in the viewing area.
The crack can be fixed with a plastic welder.
OR
can be fixed by sandwiching it between to acrylic pieces and using a two part blend to melt the seam chemically. It takes some practice though. This way is far cheaper, but usually ugly to look at.
It's a 40 gallon tank, so it's not really big. Go to petco when they are having their one $/per gallon sale and buy a glass one.
People got away from glass as it's heavy, but quite frankly it's one of the better materials out there for tanks, very hard to scratch. But less forgiving to abuse.
I have built several large custom tanks, including the ones that go into walls...acrylic is very forgiving to stresses but easily scratches and flexes under stress.
Given the option, I will always go with glass for anything under the 500 gallon range. They are just heavy as hell.

WAbedroomponics
01-12-2012, 05:42 AM
It was free I dont mind a little work lol :-) and I dont mind ugly. So what is the two part mix?

foodchain
01-12-2012, 11:04 AM
I forget the name, your local hardware store or glass shop should have it. It's a two part deal that melts the plastic together....like pvc glue does. Clean them really well, apply and squeeze them together to make sure no bubbles....bubbles = leaks.
Put a clamp on it, and leave it alone. The solvent/glue melts the two together, once it dries it should be a nice clean line...like a seam. Some tiny bubbles are inevitable, but big ones are bad.

WAbedroomponics
01-12-2012, 11:42 AM
Ok I think I know the thing your talking about I will try it. Would 4000 grit wet sand paper work to get rid of hazy really fine scratches? Thanks for all the help

WAbedroomponics
01-12-2012, 11:44 AM
Ok I think I know the thing your talking about I will try it. Would 4000 grit wet sand paper work to get rid of hazy really fine scratches? Thanks for all the help

foodchain
01-12-2012, 12:43 PM
No, there's a polishing kit you use.
You can attach the buffer to the end of a drill or use a DA type sander with buffer. But it distorts a little. If the scratches are really deep, use the 4K grit wet sand paper, or finer. But was good before buffing. The sand paper will make it look worse at first, whatever scratches you put in, you have to buff out. Use lots of compound, not just regular buffing compound but the stuff for acrylic glass. Cheapest way is just buy it all in a kit. There's lots of variations out there.

commander
01-12-2012, 02:41 PM
Harbor Freight makes a headlight polishing kit that is basically just an acrylic kit.

WAbedroomponics
01-12-2012, 04:10 PM
The scratches are really light so maybe the habor freight kit should work is it safe for fish?

WAbedroomponics
01-12-2012, 04:47 PM
Because only the inside is scratched

foodchain
01-13-2012, 05:43 AM
It doesn't matter if the kit is safe for fish. Your kit isn't coming in contact with the fish.
Polish, then clean it up.
Rinse well with plain water....when in doubt sterilize/clean with a high salt concentration.
Rinse again.
Good to go.

WAbedroomponics
01-16-2012, 01:21 PM
Thanks guys!!!!!!!!!! I used 400 grit sand paper to remove the deeper scratches and then used a headlight restorer kit to clean the rest up and now it looks truely like new. I patched up the crack with E-6000 and a peice of plexi. again thank you soo much!!!!!!! the tank was free and i only spent 14 bucks on the repairs :D