Worried About 2 Of My Girls

[Ny82]

This morning I put the light on to feed the gang and one of the hi fin females has a chunk out of her dorsal fin I have no idea how it happened. Tried to get pics but she moves so fast. She doesn't appear to be in any distress and she's eating well.

The other fish are 3 platinum tetras (who were being chased by some of the females yesterday) and my male siamese fighter who just does his own thing. I have never seen him be aggressive towards the platies.

Another concern is the big black female. Yesterday I noticed she was stuck upside down between the pebbles and the slate. I don't know how long she had been there but I had to put my hand in and free her and she's been behind the amazon swords since. She didn't come out for breakfast a few minutes ago I seen her come out but as soon as I went near the tank to see if she was ok-she darted away behind the plants again. I think she is traumatised from her ordeal yesterday. Shall I put some stress coat+ in?
Thanks

 

[OldMan47]

Fresh water, like a water change, is the best thing you can do for an injured fish. The fins heal quite well but may leave scar tissue. If you do not show your fish, it will not be a problem. Like you, I have never had a problem with my betta causing any damage but I am not familiar with your particular tetras. Some tetras are quite aggressive. The fish that spent time pinned will be cautious for a few days but should start acting fine after a short time. I find it best to never have a spot in a tank where a fish can be pinned but sometimes you don't find them before the fish does.

 

[Ny82]

Thanks for the advice oldman. The black female unfortunately passed away the same day
The other female with the chunk out her fin is still going strong and is eating well and very active.