The Puffer Forum

I have had my puffer for about 3 and a half years. He's usually fed frozen bloodworm or brine shrimp once a day. Last night I noticed he was emaciated or totally sucked in on his bottom half and he wasn't eating. My 6 year old fed him the night before and said he ate. He's now on the bottom gasping and totally disinterested in food.

Is there anything I can do for him or is it age? Nothing different happened with the tank. I usually do a weekly 50% water change but forgot last week (not all that unusual). I did a change last night. I'm afraid I don't have a water testing kit, hasn't been necessary til now. No-one else in the tank with him.

Any advice would be appreciated.

Looks like a test kit is in order.
Please answer ALL the above Qs in red. We don't even know what species you have here. It may be you haven't been feeding it enough meaty foods (brine shrimp has almost no nutrition). It can also carry internal parasites for quite some time. Or maybe because you haven't fed him any foods with "crunch", it's teeth are overgrown?