Who Gives A Fish Forums

My breeding pair has been super aggressive lately, chasing other fish and even nipping at them. Tank is 75 gallons, planted with driftwood, temp at 84F, pH 6.5. They're about a year old, fed twice daily with frozen bloodworms and pellets. Anyone dealt with this before?

Yep, mine did the same thing when they started spawning. They get super territorial. Maybe try rearranging the tank decor to break up their territory. Worked for me, kinda chilled them out.

I've seen this too. It's normal for breeding pairs to get protective, but if it's excessive, you might need to separate them or add more hiding spots. How often are you doing water changes? Clean water can sometimes reduce stress.

Mine were like that until I added more plants. They're in a 55-gallon with sand substrate, sponge filter, and lots of floating plants. The aggression dropped after a week. Maybe try that?

Aggression is common during breeding. What's your tankmate situation? If they're stressing the pair, it could make things worse. My pair calmed down after I removed the tetras.

Coralite wrote: ↑Sat Jun 21, 2025 9:38 am I've seen this too. It's normal for breeding pairs to get protective, but if it's excessive, you might need to separate them or add more hiding spots. How often are you doing water changes? Clean water can sometimes reduce stress.

Agreed. Water quality is huge. I do 30% changes twice a week in my breeding tank, and it keeps everyone calm. Also, what's your lighting schedule? Too much light can amp up aggression.

Mine were nuts until I added a divider. Now they're in half the tank, and the others are safe. It's a 60-gallon with a canister filter, temp at 83F. They've spawned twice since, but no more attacks.

Sounds like classic breeding behavior, mate. Mine were the same, but adding more cover and dimming the lights helped. Also, try feeding more often—hungry fish get cranky. What's your feeding routine like?

Lol, mine were so bad I had to move them to their own tank. Now they're in a 40-gallon with just a few snails, and they're way happier. Sometimes you just gotta cut your losses and give them space.

Thanks for the advice, everyone. I'll try rearranging the decor and upping the water changes. Hopefully that cuts the aggression.