plywood tank no pics just an idea but need help

[all_or_nothin]

im looking at plywood tanks and i want a 6ft x 3ft or maybe 2.5ft x 2ft and i looked in dads garage and for hundreds of 2x4's and like 3 10ftx5ft 1/2" thick pieces of plywood. and the tank would be saltwater. so how thick should the glass be and what would u recommend for a sealent? thanks for the help

 

[BadOleRoss]

I assume from your dimensions that you are looking at a depth of 2.5' so you are looking at 1/2" glass. As far as sealants, liquid rubber, pond coat or pond armor. There is a plywood tank build sticky at the top of the DIY section, you might want to read through a few builds to get some ideas.