Fertilizer dilemma

[nogreenthumbs]

Originally Posted by Roberta

Calcium carbonate or calcium sulfate I would expect. That's why you have a water softener indoors... replaces the calcium with sodium which is why the output is great in the shower but kills plants. So I think you would do fine just adding back a little tap water into the RO that you use for watering and fertilizing. No need to get fancier than that.

The softened tap water with the sodium from inside the house or the unsoftened tap water without sodium from outside the house? I would assume the unsoftened.

If there's a TDS meter available, then maybe experiment to find an amount that gives some DS, but not too much, ie, 1 cup per gallon or something like that.