how much gravel do I really need for a 90 gallon tank. I know the rule of thumb is something like a pound per gallon, but a 75 and a 90 have the same bottom footprint. so do I need 40lbs, 60 lbs, or more like 80 lbs??
I am looking at mixing a couple different colors to make my own mix and can't figure out how much I need to buy.
I am looking at mixing a couple different colors to make my own mix and can't figure out how much I need to buy.