Normal guppy behavior?

I am sorry for such a dramatic loss in such a short period of time. I wish you the best of luck next time.

I sometimes feel so bad for female guppies. They usually have such a short life span compared to the males. I went through a very similar experience when I first started fish keeping. I just recently tried to add females again. I took extra precautions. I added more plant coverage, used a high female to male ratio, avoided buying any females that look like they are ready to pop with babies (the stress of moving to a new home, being harassed by males and getting ready to give birth isn't a healthy combo).

As a small note, it is common for some females to group together. It reduces the chances of one female getting harassed by several males at a time. I actually noticed one of my female guppies following my female platy around. My female platy lets no species of male within 3 inches of herself. She will nip the males away. They all know to stay away from her.
 
I'd recommend getting a small 1 or 2 gal tank for a QT period.

Also, besides doing a temp acclimation, add a little bit of the tank water evry 15 minutes or so, to help the adjustment.
 
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