I will be searching for black...You should see the five black ones roaming my tank. Two are the size of dill pickles (if one was green I'd call him Pickle Rick!), one is about 6" in length and the two large ones are full on turd size at this point.
Those two like to constantly stretch up and clean the sides of the tank. I think the two smaller ones find it tough to compete food-wise with the other three.