Uh oh... CRACK!!!

[gmann1139]

I came home today to see my 29 gallon tank's level about 1" low. Thinking nothing of it, I topped it off, thinking I'd just left it a little low and evaporation had done the rest.
Well, after filling it up, I look over on the side of the tank, and see a long, thin salt creep down the side. Knowing this is bad, I wipe it off and take a look, but can't find the source.
A little later, I give it a second try, and find a tiny crack that's right about the level where the water had dropped to.

I quickly siphoned out back down to that level, and used a magic marker to mark how far the crack had gone, so I can make sure it isn't getting longer.
My question is this: I won't have time until this weekend to replace the tank. I know this is totally anecdotal, but can anyone tell me how long it usually takes until this crack becomes 'fatal?' Other than epoxy (which I don't think will help), is there anything I can do to perserve my tank?

 

[reefer545]

Using epoxy, or some kind of fast curing cement, surround the crack witha glass or plexiglass plate that is at least 2 inches beyond any point the crack measures. This has worked for me in the past. I had a 75 g. fw tank with a crack along the bottom of the tank pretty much down the middle. I just capped all the sides adn bottom with a new piece of plexi and the tank was fine for over a year. The key is to make sure you get a GOOD seal and that you surround the actual hole with at least 2 inches of space so that it dries before it leaks again. If you can keep the water level low enough not to leak then you should have no problem. But you need to seal the crack with a very tight fitting piece. The bigger the piece the more sealant you can use. Pressure upon said piece is also vital during the curing process. If you can get a real long clamp, use that to apply a bit of pressure during the curing so that when it is fully cured you dont have to worry about unbalances pressures inside the tank and out. Make sense? Oh, something like liquid nails or fishtank sealant works great. but you have to let it fully cure before exposing it to the leaking water again.
Good luck.