Hmm. Use to keep a senegal but i give it to my friend since it is already 15 cm and a 2, 5 cm cteno with 15 cm senegal will not go well most likely but yeah. Probably thinking about a senegal again especially a short body version since it is not taking to much space if i want to add other african odball.. oh yeah, sorry to keep asking about the shark, is it true that rainbow shark is a bit more docile and tolerate other fish comoare to red-fin black shark?