Help Me!!! Sick Guppy??

It wasn't just the fish store that said to cycle the tank with fish, a lot of books i've read say that too. Should I just return the fish to the pet store instead of paying $7 for a $3 fish?
that would probably be your best bet.
 
If it is just this one fish then just take it back. Unless you have grown attached in just one day.

Did you name it?
 
Lol, no, i didn't name it, and I'm not really very attached to it. It's just boring and the colors are dull, plus it's really territorial and aggressive towards any fish that comes near it.
 
Lol, no, i didn't name it, and I'm not really very attached to it. It's just boring and the colors are dull, plus it's really territorial and aggressive towards any fish that comes near it.

Well if you had named it would be died already. Just return it. It's not worth risking the other fish.
 
I have some bad news...
When I was trying to get the sick fish into a net for a change of the water in his bag, i made the mistake of doing it over the sink and the fish jumped out of the net and down the drain...
 
To isolate him just for the time it took to get him back to the store (I didn't have an isolation tank and my parents wouldn't let me get one)
 
Sorry to hear about the guppy going down the drain. :-(

Make sure you get hardy fish to cycle the tank. Guppies are not hardy fish. Danios are hardy and so are some tetras; red tetra, black skirted tetra and a few others.
 
Well, ammonia is starting to creep up just a little, but I'm not feeding my fish a whole lot to give the bacteria time to grow before they start releasing major amounts
 
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