My Black Moor Goldfish' Eyes Are Falling Out

[LucyWifey]

Hi, please can anybody help me. I have 3 black moor goldfish and rehomed them for my friend about 6 months ago, along with 2 other goldfish in my tropical tank. All my other fish one by one died, except the 3 black moors and the 2 goldfish. Anyway all has been well for quite some time, although my under gravel filter broke at one end under the gravel so I could not get the tube that end, resulting in the powerhead getting blocked constantly at one end. Anyway I was forever unblocking the powerhead so I decided to get an external filter, which was set up last weekend. The tank immediately came to life and the water has never looked so crystal. I still have one of the powerheads running for extra circulation. My husband added a few tropical fish from a friend who was moving, they all seem to get along even now which is the strangest thing, the others are much smaller than my black moors. Last night though I noticed one of them had an eye hanging by a thread. It looked awful and all I could think was that one of the other fish had attacked it. So I sat there for aaages just watching to see what was going on, none of the other fish did anything. I left them and when I checked on them before bed the eye had come off completely and the other eye looked all white as it that was going to come off aswell. Anyway, this morning the other eye is hanging by a thread and the other 2 black moors eyes are starting to do the same thing. I'm really worried about it now, the fish must be in so much pain and I don't have a clue what could have caused it. I have watched again today to see if any of the fish are being attacked and they are not. Also I have read about sharp objects but there is nothing in the tank that they could hurt themselves on. Please help, from a very distressed Lucy x

 

[glolite]

Goldfish are coldwater fish not tropical, I presume your tank is heated?
Have you tested the water quality ie ammonia and nitrite levels and how long has the tank been set up?

 

[nyx2k]

if you removed all the undergravel filter bed and added an external filter then you are starting over again with fish in cycle and if you check the stats on the water id be very surprised if you didnt have massive ammonia and nitrite levels.

goldfish and tropicals dont live together. the water is either too warm for the goldies or way too cold for the tropicals

 

[WILDER]

Size of tank in gallons or litres.
Water stats in ammonia, nitrite, nitrate, and ph.

List the full stocking of your tank.

Under gravel filters are outdated. Shouldn't be used with large fish like goldfish. As they soon block up.

Poor things.
I would add a internal bacteria med to the tank.