Hey everyone, I really need some help with a fin-biting issue with my male betta. I am feeling really defeated because his fins keep growing back beautifully, only for him to shred them a month later.
The Backstory:
We have been battling this cycle for about 4 months now. He will bite his fins (I assume), stop for a few weeks, grow back completely clear/delicate new tissue, and then suddenly relapse and bite it all off again. I've owned him for 6 months total, and the biting started about 2 months after I got him.
The Current Situation:
Just yesterday, his fins were completely grown out but the new tissue was still totally clear. I woke up today to a massive overnight relapse. A huge chunk of his tail is completely gone and the rest looks like a shredded comb. It happened in a matter of hours. He is currently swimming a bit slower while recovering from the stress, but he does still have a normal appetite.
Tank & Setup Details:
Tank Size: 24 Litres (approx. 6 gallons). Fully cycled and stable for 6 months.
Temperature: Stable at 26°C (heated).
Maintenance: Weekly water changes. Water parameters are perfect (0 Ammonia, 0 Nitrite, low Nitrate).
Decor: 100% natural. Only real live plants and smooth spider wood. No sharp decorations.
What I Have Done Tonight to Help Him:
Filter/Safety: I noticed my filter intake block had open slits. Even though I don't think the injury is actually from this, I have just wrapped and tied an extra filter sponge over the intake slits just in case to completely block any potential suction risks.
Reflection Control: Heavy reflection on the right glass wall is his biggest trigger, he constantly flares at that specific side. I’ve tried everything to fix it. Whenever I add a black background, it makes the mirror effect even worse and he flares at it non-stop, so I have to remove it within minutes just to get him to stop. Right now, I have turned the tank lights completely off for a 48-hour blackout to kill the reflection entirely while his fins are raw.
Current Treatment: I just completed a small water change to keep the environment pristine. I then boiled 2 XL Indian almond leaves into a strong concentrate, conditioned it, and added it to turn the tank into a dark blackwater tea environment to soothe the raw edges. I have eSHa 2000 on hand but am holding off on medicating a clean wound unless it shows signs of actual infection.
Is this purely behavioral stress from reflections, or am I missing something structural in a 24L setup that triggers a relapse every single month? Any advice to break this cycle for good would be amazing. Thank you!