My only concern about using sand is that I tend to use outside power filter on many of my breeding tanks and I've read that very small sand particles will get into the propeller part of the motor and burn them out. In a tank where I use Hydro Sponge filters this wouldn't be a problem. Just some food for thought. John ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@majordomo.pobox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@majordomo.pobox.com. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!