Original Platy being bullied-odd swimming

[White Cloud]

Hello,
I have added 3 new platies (1 male, 2 females) to my 10 gallon tank, which already had one platy. The original platy was plump and healthy, but after introducing the new platies, the original one began hiding and swimming oddly. I saw the male chase her around. Any solutions?

Thanks for reading!

 

[Coursair]

Hello,
I have added 3 new platies (1 male, 2 females) to my 10 gallon tank, which already had one platy. The original platy was plump and healthy, but after introducing the new platies, the original one began hiding and swimming oddly. I saw the male chase her around. Any solutions?

Thanks for reading!

4 Platies in a 10g ? That's a lot IME.
Check your water parameters.

 

[White Cloud]

Ammonia: 0ppm
pH: 7.2

I don't know the readings for nitrates and nitrites, sorry.

It is a little overstocked, but my parents decided to buy 3 more platies to keep my original platy company.