Hi everyone, I'm hoping that someone could please help me out. I just started keeping fish in november 2010 in my 125 litre freshwater tropical aquarium. I have had a few deaths in my tank so far, which i think was due to low PH which is sorted now and sitting nicely at around 7. In my tank i have ten neon tetras, 4 congo tetra, 1 bleeding heart tetra, 1 plec, 4 clown loaches, 5 silver tip tetras, 2 guppys, 2 platys and 1 shrimp. the problem is with congos in which 2 of them have a growth on there mouth which is getting progressively bigger. The growths almost look like warts which on one of the congos is on the side of the mouth and on the other is above the mouth. These have been visible for a few weeks and growing slowly. The fish seem uneffected otherwise, still feeding and active. I feed the fish varied diet of flakes and frozen foods. I have recently just started using seachem stability which has made the vital levels (ammonia, nitrate and nitrite) all zero, which was not the case when i was using stress zyme for the first 5 months and some of the levels were to high. Any help on this problem would be much appreciated. Thank you.