Another Sump Idea

I believe they are all the same, I just found them cheaper in Hawaii. They were from 6 1/2" to about 12". If you think you water is too deep then just add substrate and bring it up a little.

 

substrate is mud and sand right? Which instead of mud i heard you can use kitty liter from walmart. I know you have to get the unscented. but do you know if there is a special brand to get?

 

Tangster said to use the red bag wal-mart brand, and yes I am refering to the substrate as what ever is in the bottom.
Aquatic Plants for Saltwater Marine Aquariums: Red Mangrove Propagule - Aquacultured

 

To add to that, if you can't find the WalMart brand just buy whatever brand is unscented and is 100% Clay.