Imo the filter looks a little big and the output current might be too strong for them. At that size. That could cause stress and aggression. angel would do better in a tall tank, especially when the get full grown. And I personally wouldn't trust the betta. I've had some really aggressive ones.
Another thing that could be hapenin is that the intake is a little too strong for them at that size, so if they get any type of injury theyre not strong enough to get away from it. Just a thought
Well some things have changed since my last post. I did a water change this last weekend on Saturday afternoon and for whatever reason I lost the betta and a black skirt tetra. I went and bought another angelfish, much bigger this time. It's body alone is about the size of a ping pong ball or a little bigger. Good sized fish! I don't remember him looking too rough when I bought him, but it kind of looks like something has been nipping on him since putting him in the tank. Don't know what it could be. Again, the betta is gone. Just 1 angel. Would like to get another. I quarantined the platy for now, although i have seen a good few youtube videos of angel tanks with platy in them. Don't know... The platy ratio is still 1 male, 2 female. Don't know it makes a difference. Still have the same filter though too.
