What water to use for watering

There is no better water source than distilled. In order from best to worst I'd say RO and distilled are tied for first, then dechlorinated tap water, then tap that's been allowed to sit for 24 hours, and finally the worst is water fresh from the tap.

 

Just get a fish tank aeroter and some stones and bubl your tap water for 24 hours. Get a ph meter home depot has them about 30 bucks and ph at 6.5.

 

Yeah a reverse osmosis system is the same purity as distilled. The next step down is a dechlorinating filter, but that just takes out the chlorine and leaves the other dissolved solids in place.

In general RO is recommended for tap water over 300 ppm, and a dechlorinating filter is fine for tap under 300, under 200 would be better though imo.

 

I'd just fill up a jug from the RO water machines in the grocery store.

 

Any solution just about is going to be more expensive then simply ph balancing your water in the long run if your not growing a lot. Couple drops, digital ph meter and your done in about 30 seconds.

If your using a lot of water RO can't be beat.