I've got calcium deficiency in the veg room, I believe. Upper leaves have pale splotches and rust. Botanicare doesn't specify an application rate for foliar feeding Cal-Mag Plus; 5 to 10ml per gallon is recommended for the root zone.
I'm planning on spraying at 4ml per gallon--does this sound reasonable?
Fwiw calcium-25 is an excellent foliar calcium supplement, since trying it out I've integrated it into my routine and use it once a week thru week 4 of flower.
The reservoir is heavily aerated so I thought maybe iron was depleted along with Ca. The medium is Canna coco and perlite, 70/30 ratio.
I'm just getting used to ebb-and-flow. The table was flooded last night after increasing the EC and the topmost leaves look OK. The deficiency seemed to appear overnight.
The res was filled and aerated for quite a while before being put into use, I think stuff might have broken down from the oxygen. I'll replace the nute solution. I'm using GH MaxiGro; I've never seen this happen before but this is my first flood table experience.
Instead of calcium chloride (Calcium-25), I've ordered a pound of EDTA chelated calcium from customhydronutrients.com. I had forgotten how dark Cal-Mag Plus is.