I had 6 fancy guppies and 1 male betta. I was told they could be kept together but watch out for aggression. I have a 30 gallon tank and tons of live plants. One by one my guppies tales were being nipped and one died every day. I am down to 2. I have read that guppies can do that to each other too. I have never seen my guppies or my betta be aggressive with each other. I am confused.