Brought in an algea eater and he dies 4 days later. Now both of my goldfish are getting sic. Overnight I awoke to the tails and fins looking like they have been shredded amd colored veining with strange looking bumps on them. They were fine last night. What could have been brought into the tank to take them out so fast. They are spending alot of time at the top of the tank near the air stonesThe detereiation is fastly getting worse, .The water paramaters are spot on. Any help would be appreciated.