The geo needs sand. Without it's like a fish out of water. Excuse my pun.Thanks guys. To be honest, it looks like either one of those pictures, with my untrained eye...
The substrate is sand. One of my worries is that it would eat the harlequin rasboras. I don't want them being in danger or even feel threatened. It's not worth the risk for one fish. The tank is deep enough, a bit less than 3f and the rasboras stay in the upper level.
Yes, all the tanks were bare up until a couple weeks ago for all the years I've visited the shop. Now there's a couple of tanks with small natural river gravel and you can see how happier the fish are in those tanks...and the colors on them are way better...
Pretty sure it would be ok with your fish. I have Jurupari in with larger fish. One geo picks on the other. So I am splitting them.
The forum has info on tankmates and aggression. I don't agree that one by itself (no other geos) would be a problem.
But I don't want to lead you into something where this fish picks on another fish. They are cichlids and these are generally peaceful.
I doubt they would eat another fish even if large.