Strange bump on new fish- please don't be ich!

[Zakary2003]

My brother gave me a very small wild caught damselfish from south Florida for my new, still cycling nano reef, but the fish developed a small white bump on its back overnight. What is this and how can I treat it? Unfortunately the little guy is very small and very quick, so I only have one good picture of the bump at the time of creating this post. It is the only fish in the tank currently, but there are also hermit crabs and snails in the tank with it. I just added maricultured Florida liverock straight from the gulf two days ago at the same time as the fish so it could easily be a hitchhiker from the rock or from the wild fish. Just please tell me it isn't ich!

 

[MnFish1]

It looks like lymphocystis - not ich. If so its a self-limited viral infection

 

[vetteguy53081]

My brother gave me a very small wild caught damselfish from south Florida for my new, still cycling nano reef, but the fish developed a small white bump on its back overnight. What is this and how can I treat it? Unfortunately the little guy is very small and very quick, so I only have one good picture of the bump at the time of creating this post. It is the only fish in the tank currently, but there are also hermit crabs and snails in the tank with it. I just added maricultured Florida liverock straight from the gulf two days ago at the same time as the fish so it could easily be a hitchhiker from the rock or from the wild fish. Just please tell me it isn't ich!

Too big for ich and agree with lympho which is a condition and not disease. Often its associated with water quality issue as simple as elevated ammonia or nitrate and can be that of water from LFS and not yours. Assure to provide Good water quality monitored by a reliable test kit and feed nutritious food with fats such as LRS nano frenzy and mysis shrimp.

 

[Zakary2003]

Too big for ch and agree with lympho which is a condition and not disease. Often its associated with water quality issue as simple as elevated ammonia or nitrate and can be that of water from LFS and not yours. Assure to provide Good water quality monitored by a reliable test kit and feed nutritious food with fats such as LRS nano frenzy and mysis shrimp.

Ammonia is currently >0 because I'm still cycling the tank. It's around .25ppm so that could easily be the issue. I wasn't planning on doing an in fish cycle but here we are thanks to my well-meaning brother.

 

[Jay Hemdal Verified Community Expert]

My brother gave me a very small wild caught damselfish from south Florida for my new, still cycling nano reef, but the fish developed a small white bump on its back overnight. What is this and how can I treat it? Unfortunately the little guy is very small and very quick, so I only have one good picture of the bump at the time of creating this post. It is the only fish in the tank currently, but there are also hermit crabs and snails in the tank with it. I just added maricultured Florida liverock straight from the gulf two days ago at the same time as the fish so it could easily be a hitchhiker from the rock or from the wild fish. Just please tell me it isn't ich!

Agreed that looks too large to be ich (unless the damsel is like a quarter inch long).
This is either a cocoa damsel or a Beau Gregory. They get huge, brown and really mean!

Jay

 

[Zakary2003]

Agreed that looks too large to be ich (unless the damsel is like a quarter inch long).
This is either a cocoa damsel or a Beau Gregory. They get huge, brown and really mean!

Jay

He is really tiny. 1/4 inch might be accurate.

 

[Jay Hemdal Verified Community Expert]

He is really tiny. 1/4 inch might be accurate.

Well, if the spot drops off and new ones pop up in different locations, it might be ich.
Jay