What are common size tanks in foot?

8ft tanks are not common. That's a big tank. What are you planning on putting in it? They're not going to be cheap, so unless you can find one used at a garage sale or craigslist, you might have to go with something a little smaller. Actually, go get some silicone, putty whatever....glass, wood and start building! :)
 
Building a large tank out of plywood (with a glass front) is less expensive than buying or building an all-glass tank. Sometimes you can find really good deals on used tanks though, just have to have the $$ when it comes along.
 
The biggest tank I've seen at a LFS was a 300G.
 
That's around $250 USD, may be a good deal depending on the actual dimensions. Also figure the age/condition of the tank, and whether anything else is included.
 
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