I have a 20 gallon tank with 6 guppies, 5 neon tetras, 2 long black skirted tetras, 1 dalmation Molly, 1 cremecicle Molly, 1 silver Molly, and 1 pleco. I have no idea what is on my silver Molly I don't know if it's getting bullied or if it's ick. I need help!! It has white spots on it's fins...