I like the fact that they school especially when in a big tank. I've had KKP's and regular Parrots before with my rays and Aro...not liking the look of them...too many comments from folks thinking my "gold fish" looks cute ...LOL
1. they eat all the small particles in the water
2. they eat ray crap
3 brake up aggression
4. they are a good indication if your water is good or bad as bad water hits them 1st
5. they are cheap