Mandarin Dragonet Died of Brook

[ReeferMadness710]

Recently I purchased a Male Mandarin Dragonet and put into my tank. I didn’t QT because I read a lot of threads saying this is a fish they don’t QT and I have a female that I didn’t QT and everything was fine. Turns out 2 days later he is covered in spots, then the spots go away and he develops this batch on this right ride on the top of his fin. It got white and looked like it rotted away and his skin slide off his body. I took him out of the tank. He later died. I’m assuming now I have Brook in my tank. I just noticed some flashing on my clown fish. Should I take them out and run them through a copper treatment and wait the life cycle to re add them to my tank or should I just wait and see what happens and make sure they keep eating and fight it themselves. I know that is what to do with Ich, not sure how Brook works. Thanks for your time.

 

[Jay Hemdal Verified Community Expert]

Recently I purchased a Male Mandarin Dragonet and put into my tank. I didn’t QT because I read a lot of threads saying this is a fish they don’t QT and I have a female that I didn’t QT and everything was fine. Turns out 2 days later he is covered in spots, then the spots go away and he develops this batch on this right ride on the top of his fin. It got white and looked like it rotted away and his skin slide off his body. I took him out of the tank. He later died. I’m assuming now I have Brook in my tank. I just noticed some flashing on my clown fish. Should I take them out and run them through a copper treatment and wait the life cycle to re add them to my tank or should I just wait and see what happens and make sure they keep eating and fight it themselves. I know that is what to do with Ich, not sure how Brook works. Thanks for your time.

While it could be Brooklynella, your mention of "spots" makes me wonder. Brook typically looks like sheets of mucus. Mandarins can produce lots of mucus for other reasons, so without a microscope, you may not be able to say for sure what it was. Copper doesn't seem to work well for Brooklynella, formalin is better.

Do you see any lesions or spots on the clowns, or just flashing?
What other fish are in the tank?

Jay