What should be a maximum ppm?

[senorx12562]

I don't have a clue!

(For one thing, it will depend on ppm in your water...)

You could increase the dose very gradually, then back it off when tip burn starts to show.

a) I would do this on a test plant or 2, not the whole crop

b) Personally, I prefer a more conservative feeding plan. Less problems with buildup in the soil, better taste, etc.

I've found that running hot nutes in soil requires a close eye on soil moisture. As the soil dries out, the unused nutes become much more concentrated.

A safe nute level with moist soil can burn as your soil dries out. Just my experience, YMMV. Hermie :thumbsup:

My tap water starts around 200 ppm. If you see my posts re horticultural oil in this forum you'll see why I'm asking. Essentially, I od'd my plants on nitrogen by using a fish oil based product to kill spider mites, not realizing that fish emulsion is used as a fast acting cure for nitro deficiency, and I had just fertilized the day before. Voila, a ppm reading in my runoff of over 2000ppm. I spent 6 hours today flushing all of my plants, and was wondering when to stop. No one responded, so I got most down to below 1000 ppm. I actually flushed them so much I had to add soil to cover up the grodan cubes.