Hello Francine You could just apply a thin coat of silicon to the back wall of the 55 and add the sand to it. This would be a permanent thing but then you could add your driftwood, rocks and plants in the tank to give you that real underwater river bank look. I"ve seen this done by people that have those kind of tank set ups and it looks cool. John ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!