Who Gives A Fish Forums

My betta's fins keep tearing and I'm not sure why. Tank's a 5 gallon, heated to 78, filtered with a sponge. Water params are good, 0 ammonia, 0 nitrite, 5 nitrate. No sharp decor, just live plants. What am I missing?

Could be the filter flow. Even sponge filters can be too strong if the bubbles are aggressive. Try baffling it with a piece of sponge or adjusting the air pump. Also, check if they're biting their own fins, some do that when stressed.

Yep, flow's a big one. My dude was getting pushed around till I dialed it back. Also, what kinda plants? Some have rough edges you might not notice.

goldfish wrote: ↑Sun Aug 24, 2025 2:30 am Yep, flow's a big one. My dude was getting pushed around till I dialed it back. Also, what kinda plants? Some have rough edges you might not notice.

Totally agree. Anubias leaves can sometimes be rough on delicate fins. Maybe swap for java fern if that's what you've got.

Fin biting's worth considering too. If the tank's too bare or they see their reflection a lot, they might start nipping. Adding more plants or a background can help. Also, how often are you doing water changes?

Thanks for the tips, everyone. I'll try reducing the flow and check the plants. Water changes are weekly, about 25%.

Might wanna bump those changes to 30%. Some bettas are super sensitive to buildup. Also, what's the diet like? Poor nutrition can make fins weak and prone to damage.

Agree on nutrition. High-quality pellets with occasional frozen or live food can strengthen fins. Avoid overfeeding though, it messes with water quality.

Check the filter intake too. Even if it's a sponge, if the suction's too strong, it can catch fins. Had that happen once, was a nightmare.

Yo, same thing happened to my betta. Turned out the heater was too close to the surface and he was brushing against it. Moved it lower and problem solved.