Zebra Danio Deformity. What's Wrong With Pete?

[dfanod]

I have a glo-fish (zebra danio), and a couple of weeks ago, it looked like his forehead was getting larger than normal. Now it is double the size, and it is affecting Pete's swimming. He otherwise seems to be fine. He's eating well, and his behavior hasn't changed. The growth (if that is what it is) is inside his head. I've had him for over six months, and this is a recent development. I tried to post a video, but the site bounced it back. Any thoughts on this?

 

[WILDER]

Poor thing.

Need to ask some questions to try and find out what wrong.

Tank size in gallons please?
How many fish and which type?
Water stats in ammonia, nitrite, nitrate, and ph?

Does the swollen area look like fluid, or look solid.
Does his tummy look swollen,or does he look thin?
Or have a sunken in belly?
Does the fish eyes look swollen, or bulging out too?
Check his anus to see if it looks enlarged or red and inflamed?
What does it look like when the fish goes to the toilet.
Has the fish been injured, by another fish, or crashed his head on a ornament in the tank?
Does he spin in circles, or turn upside down?

 

[dfanod]

Thanks for your response. I have a 30 gallons tank with the following: 6 neons, 4 mollies & (1 baby), 3 hatchet fish, 2 corries, 4 glo-fish (including Pete), 2 algae eaters, and 2 rasboras. I can't give you any info on the water, but every time I have it tested, it is normal.

Back to Pete, the swollen area looks solid, his tummy is slim (the rest of his body looks absolutely normal), his eyes are normal, and his anus looks normal. He does not spin in circles, nor does he turn upside down. When he swims, it looks labored because he is trying to balance his head. I'm not sure what it looks like when he relieves himself, and I do not know if he injured himself. He sometimes chases other fish.

I hope this info is enough.

 

[WILDER]

Needed to rule out internal parasites as they can enter the brain of the fish.

It could be a tumour. All you can do now for the fish is isolate and try an antibiotic like tetracycline. If it is a tumour the medication won't help.
I wouldn't advise using antibiotics in the main tank due to the antibiotics destroying your good bacteria in your filter.

Maybe also preform some epson salt baths to help draw the fluids out,

Good Luck.