My fish smells like rotten eggs

[klarka331]

Today I was changing 2.71's water and I noticed I really bad smell. I cleaned out his tank and moved him from the 2.5 gal he was in temporarily back to his 5 gal. I smelled the water before I put him back in and it was fine, but shortly after it smelled just as bad! I think it must be him because I changed Sqrt's (my other betta) at the same time with the same water and his tank smells fine.

Is this some kind of illness that is making him stink, breath heavy, and barely move?

I checked the water stats and it's all normal and the temp is 79 degrees.

[Allenbetta]

You have peddles and decos on the tank,right?? That's typical I afraid. It's the residues has made the tank effluvial which daily piled on that. That's why my Betta tanks (13) have none which I have removed peddles afterward.

[Oldfishlady]

What kind of substrate and how deep and do you have live plants or other critters in the tank like shrimp and snails, what about uneaten food removal. And is there a filter or air stone in that tank, what is the cleaning schedule and vacuuming

Rotten egg smell can be bad and deadly for the fish, it is usually from dead spots. you may need to tear down that tank, but I would remove the fish and place him in a bare bottom QT for now and start make daily water changes on the fish until you get his tank figured out and fixed.

[klarka331]

He has about an inch of marbles on the bottom. I don't have live plants just plastic. He is alone in the tank. There is a filter, I change 50% of the water every week and 100% every month. I had him in a smaller tank and it smelled too.

[mysquishy]

My betta Terence has always had a strange smell to his tanks but my other bettas don't stink like that. Sorry I am no help. I would like to know why my betta is so stinky too. LOL

[Betta Slave]

One of the reasons I'm allowed to keep fish is that "they don't smell".
Hah, guess not XD