Who Gives A Fish Forums

Noticed a weird lump on my betta's side yesterday. It's kinda round, not fuzzy like fungus. Water params are good, 0 ammonia, 0 nitrite, 5 nitrate. Tank's a 10 gal, heated to 78F, sponge filter. Anyone seen this before? He's still eating but moves slower.

That sounds sketchy. My last betta had something similar, turned out to be a tumor. They're pretty common in older ones. How old is yours? Might wanna check if it's growing.

lilynx wrote: ↑Sun Jul 27, 2025 2:28 pm That sounds sketchy. My last betta had something similar, turned out to be a tumor. They're pretty common in older ones. How old is yours? Might wanna check if it's growing.

Yep, tumors are a bummer. If it's not growing fast, could just be a cyst. Try epsom salt baths, 1 tbsp per gallon for 15 mins daily. Keep the water pristine, maybe up the water changes to twice a week.

Mine had a lump too, but it went away after a week. No idea what it was. Maybe just a weird vibe thing. You gonna try the salt?

Tumors are often genetic, especially in line-bred bettas. If it's internal, not much you can do besides keep them comfortable. Monitor their behavior—if they're still eating and not lethargic, it's manageable. What's their diet like? High-quality pellets can help overall health.

Thanks for the advice, everyone. He's about 2 years old, got him from a local breeder. Gonna try the epsom salt baths and up the water changes. He's on NorthFin pellets, gets frozen bloodworms twice a week.

Sounds like you're on top of it. Keep us posted if it changes. Older bettas are tough, but they can surprise you.

drift42 wrote: ↑Sun Jul 27, 2025 7:04 pm Thanks for the advice, everyone. He's about 2 years old, got him from a local breeder. Gonna try the epsom salt baths and up the water changes. He's on NorthFin pellets, gets frozen bloodworms twice a week.

Solid plan. If the salt doesn't cut it, kanaplex might help if it's bacterial. But yeah, tumors are usually a wait-and-see game.

Hope he pulls through. Mine's a fighter too. Bettas are weird like that.

Agreed on the genetics angle. Local breeders sometimes have weaker lines. Not blaming anyone, just how it goes. Good call on the NorthFin, though. Quality food makes a difference.