Having problems with guppies

I acclimated them perfectly,

I acclimated the guppies perfect too, doing a float for 5 minutes, putting in a cup of tank water and wait another 5 minutes, doing the previous 2 more times, and finally releasing the guppies.

I didn't compare the store's water, but I had bought the Amano shrimp from a tank that uses the same central filtration as the guppy tank at the LFS.

I found the other female dead, which leaves only 1 more male from petsmart, and a male I had bought from petsmart about 3 weeks ago.
 
Bad stock, most likely. And actually, I think you didn't acclimate them correctly. It should be slower, over a longer period of time, with smaller amounts of water added, such as drip acclimation. IMO.
 
There's one more LFS I could try, I will probably go on the weekend. It seems like it is bad stocking. However, the other guppy from petsmart has still survived.
 
Im having the same problem my fancy tail guppies are dying like nothing. I just bought them two days ago and I have 2 left. My water parameters are great its an established tank. Dont know maybe its a bad batch.
 
Try other places to buy them, I figure out that my problem was that the days I had bought the guppies were the same days that they were shipped in, causing alot of stress on the fishes and eventually dying.
 
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