Reptile & Amphibian Forums

Hi,

I have a pretty peaceful community 40gal freshwater tank. I bought a bright red/orange double swordtail, and it got ick.I seperated it and treated it sucessfully. When I tried to put it back into the main tank, it was met with incredible aggression from the other tankmates. It was being ganged up on and attacked so badly I pulled it back out and put it back into the hospital tank. I've been puzzling over what to do.

Today I decided to follow the advice of a gal at the lfs., and I purchased one additional swordtail to introduce into the tank at the same time as I tried to reintroduce the double sword again (I also bought a pretty gold nugget pleco at the same time). So I had 3 fish to put in the tank at once. Two being male swords. I also fed the tank as I was releasing the 3 new fish.

At first I thought it had worked, but when the feeding stopped, some aggression re-emerged. The female swordtail began violently attacking the male double sword again. She grabs the dorsal fin and violently shakes/tears it back and forth. I've looked online,but can't find info on this behavior. Anyone else know what the problem is? I don't know how long to give it to see if it'll resolve itself, or if I need to pull the male again? At least it's one-on-one this time between the two of them, whereas last time everyone bullied the poor thing and it wasn't able to defend itself.

TIA
Shalori

Sounds like you have quite the aggressive sword there. How big of a tank are you putting it in and how many / breeds of tank mates are there? If the tank is big enough to support the amount of fish you are putting in it, you could try to rearrange the tank before putting the new fish in. Also try creating some hiding spots with the use of rocks or plants. Good luck and I hope this helps!
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Mike
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