Tap water is only an issue if you grow in natural organic soil without nutrients. It's fine for hydro growers; the plants won't even know the difference. Chlorine, chloramine, and flouride contained in most city tap water systems kills the microbes & fungi that feed your plants in a natural soil food web. If you are using nutes then microbial activity doesn't really matter as the plants don't need them to break down the food in the soil.
Tap water is only an issue if you grow in natural organic soil without nutrients. It's fine for hydro growers; the plants won't even know the difference. Chlorine, chloramine, and flouride contained in most city tap water systems kills the microbes & fungi that feed your plants in a natural soil food web. If you are using nutes then microbial activity doesn't really matter as the plants don't need them to break down the food in the soil.