hi. Have a 10" plec in with 10" oscar and 2 x 5" oscars. I have noticed several splits in the plecs tail, tho I haven't seen any aggresion towards the plec. There is a sizeable peice of driftwood with several "branches" sticking out. Whats the best additive to aid healing, was thinking of using Melafix. By the way, Mr plec seems quite happy and often comes up to compete for the prawns when they go in. Thanks in advance.