Stress stripes in community tank

I put a female betta in my endler's grow out tank, hopefully to curb the number of new fry. I'm afraid it might be a bit raucous for her, because when they get active (like when I come into the room or look at them around meal time) I see her stress stripes come out. When it's quiet in there she seems fine, but the commotion's not about to go away.

Will she get used to it? Is that an acceptable amount of stress for a female betta to deal with?

 

If its a regular thing that her stress stripes are appearing then I think it might be best to put her in a tank of her own.

 

I don’t think the betta is going to do very wel long term

 

I put one in my 40 gallon breeder tank, and she showed the stress stripes for a week or so, but then stopped. She's all over the tank now and doesn't seem stressed at all.

She liked to hide at first. Do you have plants or other places for yours to hide in? That might make her feel more secure.

 

It is planted and there are plenty of hiding spots, and when she's there her color's normal. But when she's out she chases the other fish away from her, and they keep their distance, but if the school gets worked up they ignore her space and that's when the stripes come out.

This is day 2-3