i can get a 75gallon for 98.00dollars. Aquriuam Adventure is sooooo..... over price on their stuff!(like 3-5times what they bought it for.) I been there, done that and even talk to the owner of Aquriuam Adventure buisnise. the One that is in my City is the largest and even their headquarters.
I did had 100lbs of Play sand in my 75gallon tank before. I got it preclean already in a plastic bag at lowes hardware store,(i will never do that again! the sand, it destroyed 2 of my 110 water filters...) and it took about a week for the sand to settle. I had about close to 200pounds of decorating stones when i use to work for a stucco company. i had 10, 5-6inch convicts (convicts they need alot of space even in alot of 200lbs stones full of hiding spots!) (it is like putting 10male lions together; they always were fighting and the winner always end up with big heads like fontosas chiclids) I pulled Poop from the bottom of my tank, It was mixed with sand it came from one of my catfish. It was had as a stinky rock!
