hi i have 12 lovely guppies and they've always been fine but i recently lost one and noticed its fin was ragged its tail was all stuck together and it seemed like it couldnt swim properly either....... i have also noticed that a few others are wiping themsleves on the gravel and a rock i have not all the time but sometimes ive seen this. So i just wondered if anyone could tell me what this is and how i treat it...i also have 2 dwarf frogs in my tank and a algae eater (altho it looks like a golden loach) it is bout 4 inches. thanx