Ok, So Im having success yay!

My 55 gallon tank is doing spectacular... YAY!! I have a question though.. My shark is a bit territorial.. Is there any kinda catfish I might could add that would do some scavenging at get some leftover flakes that wouldnt kill him but also wouldnt be tormented. I had given thoughts to a raphael cat.. but wasnt sure if he might pick off the barbs.. any ideas?

Maybe yoyo loaches. Redtails can be quite aggressive towards other fish that look similar. So if you end up getting another catfish type be cautious.

Redtails WILL be aggressive with anything but Plecos. I've had one for three years now. He was trying to be aggressive towards my Jack Dempseys. Maybe a bristlenose pleco or two would be something to try.

I have always had luck with cory cats in tanks I have a redtail.

Yeah. My cories never seemed bothered, but my redtail would take a run at them sometimes.

I also have a krib who has become more mild since bein put in the 55.. I guess cus shes not the biggest now.. I may try to find some big cory's to try and if the dont work I have a 29 they could do fine in :) may give the bristlenose a look too

botias might work. they have their subocular spines that will keep the shark away after a few tangles. I had a rowdy pleco that would chase everything away from his wafers. he learned he had to share with the botias

I have had luck with yoyo loaches in the past with a redtail as well. Wasn't even thinking about them. My redtail actually schooled around the tank with the loaches.