Nasty aggressive fish

Trishfish

Gee, Blue, you might be right. He truly is quite large and that would fit with the Swordtail. Any tips on purchasing "true" platies next time around? I will add in a few more plants too. My tank is 36" across and new so I can't add more space at the moment.

Lupin

There can't be quite many pure platies these days considering how eager platies and swordtails will crossbreed with each other. Pure ones don't really get aggressive although they are still no exception to the rule that males will chase the females around alot.

Sadie

The thing that worked for me is that I put the weaker male since he was the one suffering the rath the most into the other tank and swapped out a larger fish and put it in the trouble maker's tank and that seemed to settle him down.

Trishfish

Thanks for the suggestion. I don't have another tank with fish to swap around. He still rules the roost but has now made "friends" with the others. Occasionally he even gets chased away. There are four females and two males and a bunch of babies in there. :D