Thanks I-715. Should be enough to last us a while.

I'd been noticing some discoloration on the leaves but was having a little trouble nailing down a diagnosis. My suspicion was Magnesium deficiency. Today, the signs actually progressed to the point that I am able to say,for certain, that it is a magnesium deficiency. We had been using 5ml of CalMag per gallon which gave us a PPM reading of 200. I went back and re-read the info on the bottle and it says for hydro to shoot for 300 PPM. Since they are currently deficient, I'm thinking we'll go with 10ml for a while. That should give us 400 PPM. After the plants show that they have recovered, we'll adjust the amount of CalMag down to 300 PPM.