Male Guppy Aggression

[Easy]

So I recently got the recommended ratio of 1 male to 3 females. I had 2 males and 6 females total. Everything was fine at first but two days ago I noticed both males stopped doing the dances and chasing the females....they were both kinda hanging out near the top corner of the tank. I thought it odd and the next morning one of the males had a big hole in his back fin and wouldn't leave the corner of the tank. Now this morning he has no tail............ He is alive and just able to swim a bit but it doesn't look good. Why did this happen?

 

[PrairieSunflower]

Sounds like something I had happen not long ago.

I got a few guppies (including 2 males). Males went in the male tank and females in the female tank... by the next morning one of the males was missing a large part of its tail and more dissapeared as the day went on... by the next morning it had no tail and the tail rot was spreading to its body so I euthanized him. It was strange as it seemed like clear tail rot but the speed was very unusual.

Sorry, no good advice.. just thought I'd relate a similar experience. I tried treating for fin/tail rot but had no luck.

 

[fish48]

So I recently got the recommended ratio of 1 male to 3 females. I had 2 males and 6 females total. Everything was fine at first but two days ago I noticed both males stopped doing the dances and chasing the females....they were both kinda hanging out near the top corner of the tank. I thought it odd and the next morning one of the males had a big hole in his back fin and wouldn't leave the corner of the tank. Now this morning he has no tail............ He is alive and just able to swim a bit but it doesn't look good. Why did this happen?

your male guppy's have been attacked by a female/females.
some females can get very aggressive