I had two gold fish in a tank 1 was smaller than the other day by day I noticed that the smaller fish was losseing bits of its fins tail etc then I cleaned it out 1 day it had 1 fin left on it (poor thing) I don't no whether the other fish was eating it or it was bad! I took it out of the tank and put it in another tank, 2 days later my little fish had died do you no the cause of this??
I have one gold fish left and now that is starting to get red markings on its tail and body? Please help.