Its really hard to do without a ppm pen. You can get them for 20-30 bucks. well worth it. Your kinda working blind now. Good Luck.
So does the plant show signs that the ppm is off? I looked up the ppm on the city water site a couple months ago and I thought it was in what you would call an acceptable range. The city says the water "hardness" range in my area is about 120 to 220 ppm. Can I go with that, or do I really need the meter. Thanks for the input.