R/O water. Where to find?

I see online that I can purchase a filter and while that will probably be the most cost effective route and I will go that way in the near future, can I expect to find reverse-osmosis water in a local store perhaps in a gallon? I no longer shop at WalMart though I know they didn't carry it and I haven't seen it in a Publix.

Thanks:thumbsup:

Almost any aquarium shop that carries salt water fish will sell RO. However an e-bay RO filter will save you money in the long run.

The shop I used to buy it in (for my aquarium, before I bought a filter) sold it at $0.50 a gallon.