betta ripping gups tails

[kelbear]

hi everyone Im new to the forum but.not to tropical fish keeping.

I've had my fighter in my 70litre set up for a year with 2 male gups. for a whole year he has not taken any notice until now. he seems to have been attacking there tails at night when the lights turned out because in the daytime he takes no notice of them.

i just can't understand why he has changed all of a sudden. no changes to the tank the water is spot on according to my api test kit. looks like Im going to have to move my gups.

 

[bettaowner]

Male bettas fight with guppies because the guppy tails resemble betta tails.

 

[Cynic]

It's a common story, you'll often hear "I guess I'm just lucky as my betta is really placid towards my other fish" only for a few months down the track things to go down hill as yours has. Rehome either the guppies or the betta.