What’s wrong with my fish?

just_use_soap · Dec 8, 2025

I’ve had this Citron Goby in my tank for 1 month and it didn’t show any signs of illness until about 2 weeks ago. It started to have these little white dots, I thought they were just mucus cysts because my research told me that Citron Gobies can struggle with that. He would be completely free from spots sometimes, and other times he’d be covered in white spots. I’m not sure if it’s Ich or Marine Velvet, I don’t it’s marine velvet because from what I’ve researched it can kill a lot faster than 2 weeks. Now I think my Black Snow Clownfish might have it, not sure what to do. Gonna put it my QT setup since I can’t dose copper or other chemicals (it’s in a 32 biocube reef tank right now). Not sure what to do, maybe I should pull all of my fish, but I don’t know. Any help or identification would be great. Pictures below \/

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Jay Hemdal · Dec 8, 2025

just_use_soap said:
I’ve had this Citron Goby in my tank for 1 month and it didn’t show any signs of illness until about 2 weeks ago. It started to have these little white dots, I thought they were just mucus cysts because my research told me that Citron Gobies can struggle with that. He would be completely free from spots sometimes, and other times he’d be covered in white spots. I’m not sure if it’s Ich or Marine Velvet, I don’t it’s marine velvet because from what I’ve researched it can kill a lot faster than 2 weeks. Now I think my Black Snow Clownfish might have it, not sure what to do. Gonna put it my QT setup since I can’t dose copper or other chemicals (it’s in a 32 biocube reef tank right now). Not sure what to do, maybe I should pull all of my fish, but I don’t know. Any help or identification would be great. Pictures below \/

Welcome to Reef2Reef!

That’s marine ich. Gobies show it a bit differently than other fish do. This is an advanced case with signs of secondary bacterial infection. You are going to need to treat all exposed fish in a tank with NO corals or other invertebrates ASAP. The two treatments are: coppersafe or hyposalinity. I can walk you through either one