White Spot / Lump On Dorsal Fin

[Ryefish]

I was checking my fish yesterday and noticed this on the dorsal fin of one of my Cory's

There was a reading of Nitrites yesterday and i carried out around 30% water change but im not sure if it is just a false reading caused by my plant ferts. I haven't dosed plant ferts yet today and there is 0 Nitrites. I cleaned the filter on Tuesday and changed about 20% of the water (normally a weekly routine)

I added three more Cory's and 20 shrimp to the tank a few weeks ago but this one albino cory is the only one to show signs of anything, and none of the newer fish had/have any white spots on any part of them. There are five cory's overall, two albino and three bronze


Any ideas? If it needs treatment, i will have to pull it out the tank, but should i just take one or all the cory's out?

 

[Athena]

Hm, not sure what that white blob can be. Fin rot?

Is it my imagination or is this cory also looking a bit front-heavy? Can't quite put my finger on it but there's something not quite right...it looks too rounded underneath...could be wrong though!

Athena

 

[WILDER]

Has the lump just suddenly appear.

Does the lump look hard or soft like filled with fluid.
Any redness or pinkness to the lump.

All you can do is isolate and try a bacterial med.

Lumps can be viral lymthocystis, bacterial, caused by parasites, tumours.

 

[Ryefish]

Yes it just suddenly appeared and looks hard. No redness or pinkness, its just opaque white. I need to find a container to put the fish in. My spare tank has fry in it.

Im not sure about the front-heavy bit. The fish has always looked like that. It's one of the biggest fish in the tank and the largest Cory i own - atleast half an inch bigger than the other adult one

 

[WILDER]

Just keep a close eye on the lump that it dosn't change shape. Caulifower looking.

It's best to isolate fish with lumps incase they burst and infect the tank.

Can't you risk moving the fry to the main tank?

 

[Ryefish]

im more worried about the fry getting sick if there is something contagious in the main tank, and i have baby apple snails in with the fry. I was going to put them in a breeding trap (they are big enough not to fit through the gaps now) but i am a bit about it now

Im going to pick up a new container the Cory can live in until this mysterious thing dissapears

 

[WILDER]

You need to try a bacterial med for the lump.