PH - how much acid or alkiline is your nutes
PPM - parts per million of disolved solids.

two different things. both should be considered.
Opie Yutts Reviewed by Opie Yutts on . PH tester I called my local garden centre to get a price for a digtal PH tester. Their cheapest one was $89, can you get any other digtal tester that isn't so $$$ and still good quality? Rating: 5