lump on Pea puffer

[Steven Horwood]

Pea Puffer has large lump on its side causing it to be buoyant.I first noticed it one month ago.I isolated it in a fry netted coral .It didn't eat for about 2 weeks ,became paper thin.i noticed at this time the lump had gone away .At this point it strteded to take live blood worms.The fish put on considerable weight and was swimming normally. Now it is plumped up the lump is back and is continually on the surface due to the lump keeping it buoyant.He willing to eat but finds it difficult chase the food as it falls due its buoyancy.
worms ?
tumour ?
I have had him for almost 5 years and he is about 1 1/4' long

oh what to do ?

 

[Sgooosh]

Pea Puffer has large lump on its side causing it to be buoyant.I first noticed it one month ago.I isolated it in a fry netted coral .It didn't eat for about 2 weeks ,became paper thin.i noticed at this time the lump had gone away .At this point it strteded to take live blood worms.The fish put on considerable weight and was swimming normally. Now it is plumped up the lump is back and is continually on the surface due to the lump keeping it buoyant.He willing to eat but finds it difficult chase the food as it falls due its buoyancy.
worms ?
tumour ?
I have had him for almost 5 years and he is about 1 1/4' long

oh what to do ?

photo?