I have four oscars, 2 are tiger oscars and the other two are albino tiger oscars. My smallest oscar has suddenly become very agressive and I am trying to figure out how to stop it. My only other alternative is to get rid of her. If anyone has any suggestions or can help it would beappreciated.

welcome to the site.

now to start with how big is your tank? what kind of filtration are you using? have you tested your water for ammonia nitrites and nitrates? and if you have could you post the results. if you can get these answers to us we can eliminate a few reasons why an o might start being aggro. also are there any other tankmates in with them?