Ok I need some info on tank size for a red tailed shark, they get from 4-6 inch's, My moms friend has one in a 55 gallon with 1 silver tipped shark full grown (did have 2) 2 cichlids not sure of what kind, A Synodotis catfish and another type of catfish not sure of its type either, ive read serveral websites, one sugested 10 gal or bigger which is ridiculous, one said 20 gallon or bigger which i stil find a lil outragious, then 1 said a 30 gallon and another said 50 gallon. Can anyone tell me if it can fit in a 30 gallon sand bottom? Aqadvisor says its fine just warns me to keep tight lids which i always do sense my mom lost fish to loose lids. His tank mates would be a Pseudotropheus Acei and 5 pictus catfish, which doesnt worry me sense every website i checked did say it was possible to keep him with similar sized tropical fish or cichlid's. Anyone who can help me with any info on these fish please do i promise im not gonna lash out at you