Help Me!!! Sick Guppy??

Well, from what I've seen so far the guppies are doing fine, and the guy at the fish store who knew his stuff said that the guppies will be fine as long as i do frequent water changes.

I was thinking of getting something like Stress-Zyme or Cycle so that some of the load would be taken off and the fish would be fine. Is this a practical solution?
 
Nope. Bottled bacteria does not contain any bacteria at all. For the bacteria to survive shipping/stocking it has to be cooled so the colony stays dormant. Only thing that works is Bio Spira although I'm not sure if the current stuff being sold even works...

Test your water frequently and do water changes to keep ammonia and nitrite below .25 ppm. The lower, the better.

And a pearl gourami was a horrible suggestion for a cycling fish. Well, I think suggesting fish cycling is bad to begin with...
 
Do you think I should take the fish back, or just stay with the fish and continue to cycle the tank with them in it?
Keep in mind that the aquarium store is a good bit out of the way...
 
I would take them all back and go with a fishless cycle. If you still want to cycle with fish you could try using just the guppies, although I can't imagine that it would go well. Danios are the staple fish cycler, unfortunately.
 
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