Female RES eating male RES tail!!

Question
I have 2 RES, a male and a female there approx. 1 and a half years old. The female has been very aggressive towards the male for awhile. She bites at his feet and tail. I left for the holiday weekend and when I got back today the males tail is almost completely gone!! He's just sitting on the dock, not really moving with his head laying out. He's not responsive to movement and when the female bit him he just sat there and didn't try to get away. Is the female trying to kill him? Is she made because he's been trying to court her? I took the female out and put her in a seperate tank to see if he gets better. Let me know if this is something you've heard before and what I should do, thank you

Answer
At about a year and a half, they are not mating, this is dominance/aggression/territoriality behavior, possibly due to an enclosure that is too small for the two of them.

The male sounds badly stressed. You'll need to separate them and keep him in a warmer, very clean tank with no stress. Swab the injury with Betadine Solution. Let it dry for about 2-3 hours before returning it to the water.

Make sure the male is OK before reuniting them, and make sure the shared tank is big enough.

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