Really? That would be cool, I am hoping you don't mean RTCats. The Redtail Sharks were always my fave as a kid, when my old man had his tank, (Mid 1970's). how many do you think for a 125 with my guys?? (See sig) Also Thanks to peanut as well! Do you think I could Combo RTSharks and a couple of Clowns??
Definitely not a redtail cat. That would eat all the fish in the tank and drag you in to eat you too.
These redtail sharks are great. This page says they get to be 6" long though! These pages also say that clown loached get really big too but i've never seen them overly large. They are also very thin and narrow so they aren't a huge bioload. Very snappy little guys, they nip at other redtail sharks and should be snappy enough to keep from getting mauled by the cichlids. I am going to get some for my 125 in my sig (maybe 4) I think there are also another type that look very similar, maybe they don't grow as large.
I'm not an expert on these guys though so i'd suggest you look for other opinions also.