by DanRad on Thu Apr 05, 2007 10:11 am
Couple of things to bear in mind about "sharks". The "shark" that has been in the hobby the longest is the black shark. Nice, peaceful fish, but they grow to well over a foot long, and eat like there's no tomorrow The red-tailed black sharks and the "rainbow" sharks top out at around 6". They can be rather territorial, so you want to be careful about space if you're going to get more than one. They both do some algae grazing, but are omnivores. Bala sharks get much bigger (around 12"), like to be in groups, and will cheerfully eat smaller fish if they fit in their mouths. Iridescent sharks (actually a catfish) look very pretty while they're small, but can grow eventually to around 3 feet, and lose that green color. Omnivorous, but not aggressive, they're quite shy -- even prone to panic, and can hurt themselves by crashing into the ends of the tank. The so-called "Paroon" shark is also a catfish, and also grows prohibitavely large. There is also a "silver shark catfish" or "Colombian shark" that is more obviously a catfish, but as it grows and matures needs more and more salt content in the water, eventually requiring full marine conditions. I've also seen a fish called a "blue shark" that really does look like a shark, but is in fact a catfish. These are somewhat parasitic, in that they feed by biting circular chunks out of other fish.