Currently im using a white really fine sand in my tank with 1 Jack Dempsey (3 1/2 inches) and a few bottom feeders, i notice he tends to turn a yellowish color like hes trying to blend in with it and i heard if you use Black sand he will probably try to blend in more with that making him a dark brown (which is the color i want him) anyone know if this is true before i go buy bags of sand? lol any opinions would be great!