I did a water change recently and every few weeks I'll test my water... well this time I tested for ammonia the day after the water change and it was really high even though it was a 100% water change in a 2.5 gallon with one betta! So I thought well... it's a strip test so it must be off. I took some sample fresh off my faucet to my pet store (I feel bad, it's the second time I do this in a week ^^;) and they tested it and it turns out the ammonia levels are pretty high (I forget what number he said sorry ><) there too. He then tested his own water off the faucet at the store and it was high there too. I don't know what's going on, and maybe it's just an error, but it seems to be a local thing. I'm in the Pembroke Pines area so if you are nearby it might be worth it to check out your water parameters. Also, our pH is super high... like 8.2 or something, did you know that?
I've tested it before and have gotten a pH of 7 though.... I wonder if distilled water would help? My pet store sells it pretty cheap.