How do you figure out how much gravel to buy?

[NinjaSmurf]

I want to start up a 55 somtime in the future, and I'm making a list of all the things I'll need for it and the prices, but I want that tropic isle Tahitian black moon sand, which is 13.99 for 20 pounds. But I don't know how much I'd need to cover the floor of the tank with about 3/4 inch of sand. Is there a way to figure this out?

 

[FishEnthusiast]

My lfs told me 1 pound per gallon. I have found this to be a pretty good measure. When I set up my 55G I bought 50 pounds of gravel and 10 pounds of flourite. This did a pretty good job of covering the bottom. I used really small gravel. I am not sure if it is different with sand.

 

[wrs]

usually 1-1.5 lbs per gallon, sand included.

 

[NinjaSmurf]

Gah!

Oh well... I gotta have my black sand... besides, that's leave me with some extra.... Muhahaha....

 

[squirrelrabbits]

There are some nifty substrate calculators on the web that help you figure this out for sand, gravel, flourite, etc. They let you add a lot of variables--depth, size of tank, gallons, and so on. Just google "substrate calculator" and see what you find.