The Puffer Forum

My F8 puffer seems to be thriving in his tank. He's adorable and begs for food whenever we go near the tank. He only really likes snails and brine shrimp, but will eat blood worms, too. When he eats each night, he gets nice and round in the belly, but by the next morning, he's fairly thin.
Also, when I was cleaning his tank yesterday, I put him in a holding tank (was changing substrate, so I had to move him) and when looking straight down at him, I noticed that his spine is curved. Looks just like an S. You can't tell anything is different when looking at him from the front or side, but it was pretty obvious from the top. He swims great (and fast!) and is always hungry... is this normal or is he hurt/deformed?

How big is his tank? Sometimes fish develope warped bones from too small a tank - he needs at least 15 gallons. Also, malnutrition might cause it. Have you had him since he was a baby? If he was being fed almost entirely brine shrimp at some point in his life, or perhaps keeping himself alive in flake(though many will starve before taking it), he might have gotten malnourished and developed a deformity. He also may have been born with it, and is just a trooper thriving under good care in spite of his bad start.

He may also have internal parasites & the sunken belly will give the appearance of a curved spine. How long have you had him? Also, check our Library for other food ideas.

If this is the one in a 5g tank, its possibly from being stunted.