The only thing about bottle water is that it doesn't contain the minerals from tap that is needed for your fish. You can still use it, but remember he might not do as
well but it should be fine for temporary.
There are a few things you can get, SeaChem's Prime Water Conditioner also neutrifies ammonia coming from your tap so what I would do is get a bucket, fill with some tap water, use Prime and check the ammonia again. Here's the site link for Prime so you can check out exactly what it does: http://www.seachem.com/Products/prod...ges/Prime.html
You can also use something like this: http://www.petsmart.com/product/inde...9-001b2166c62d
Again I would take a pail of water and test it again before you use it in the aquarium just to make sure.
And whatever you do, don't use distilled water please! That stuff is very harmful to your fish :)