I know they say each strain differs but is there a baseline ppm level I should keep my res at?
Ya sure. I highly highly recommend using RO or distilled water too -- my advice doesn't mean anything unless you have that because that's what my advice is based on.
We'll start with veg.
5mls per gallon or 250 -300 ppm of calimagic will always be your base -- always. For example, if I say 500 ppms at a particular stage, that means the 250-300 ppms of calimagic, as always, and then the rest of the 200-250 ppm is is made up with EQUAL portions of grow, micro, bloom until you reach the 500 ppm.
I use only the calimagic base, 250-300 ppms, until the roots go down into the water; you can either drip feed or raise the res water to an inch above the bottom of the net pot until the roots hit the water. Then you lower the water to about an inch or two below the net pot.
Early veg. weeks 1-2 300-400 ppm
Mid - late veg weeks 3-6 400 - 550 ppm ( 550 can accommodate a HUGE plant in veg, that's really the maximum you'd ever need to go in veg.)
Flowering you'll start a 6-9 ratio that will replace the 1-1-1 ratio ------- 6mls of micro and 9 mls of bloom, no grow. Calimagic @ 250-300 ppms is still your base.
Early flower weeks 1-3 550-650
Late flower weeks 3-6 650-850 (I finish most strains in dwc under 700 ppms, so 850 would be a heavy feeder)
That's a general guideline that should keep you in shape but as you said, each strain differs and you'll just have to keep a good eye on the ladies -- there's no substitute for experience.
