It's definitely fixable. You will need to make sure your replacement glass is the same thickness of the glass that was in it. You will also have to make sure your silicone is aquarium safe. I always just buy the silicone sold at the pet store. First you clean all the old silicone from the area of the broken glass and make sure you have no old silicone left. I think you can use rubbing alcohol to make it squeaky clean. Next, you simply silicone all the edges, especially the corners and let it dry for about a week. Then you should put water in it and let it sit for a week to check for leaks. Some folks will also tell you that you need to strip all the silicone from inside the tank because the new silicone will not stick well to the old silicone, and you will have a weak spot which will eventullay leak. And don't skimp onthe silicone. You can smooth the edges which are visible from the outside of your tank, but make sure it's pretty thick in the corners.
your instructions are exactly what I was looking for.
However, I was inspecting the tank, and I've noticed that there are appears to be two different kinds of silicone; one lines the bottom (clear gray) and the other is used to seal the area where the glass sections come together (black). Is it crucial that I buy two types of silicone, one replacing the gray the other the black?
The tank is a rectangular 28 gallon; how much do you think a 36'' x 19'' piece of glass + silicone would cost...would it make more sense to invest in a new tank?
I believe that silicone comes in different colors. All the reading I have done when I repaired our 110 tank don't indicate any different types of silicone used, but that there are different colors. I used the clear silicone.
boy you guys are courageous!! If mine had a huge crack I would get rid of it. I see lots of times in the thrifty sections of the newspapers they sell tanks ect very cheap. Or I would go to wall mart and check. I think their max. size is about 55 gall so may have to go elsewhere but they come with kits including filters, heaters, ect which can really save a lot of $$. I am thinking about repairing a 15 gall that a friend gave me. It holds water but the 2 rI'm things are cracked. I can get them at the fish store for about $10.00 but don't know if they would be hard to get off or replace. Keep an eye out in the paper or a garage sale you may find a bargain...
Normally I would just get a new tank, especially after realizing the work involved, but I bought the 110 gal. off ebay, and knew it had a leak when I bought it. I doubt I would buy another tank in this condition again. It's a lot of work, and if you don't get the seal just right, it's gonna leak. We've learned the hard way.