RO water, cal mag ppm?

[MHHSP]

Hi all,
I am a soil grower, however do to issues with my water quality I have made the switch to using RO water.
So question for all the hydro guys,
With straight RO water I want to add cal mag every watering to correct the water chemistry right? I have cal-mag plus from bonicare, its 3.2%Ca, 1.2%Mg, .1% iron. So the tricky part is I do not have a tds meter, is there a way I can add x amount to every gallon RO water to achieve desired ppm? Guessing around 120-200 ppm?

Thanks!

 

[!!!]

Add calmag if your plants tell you they need cal and/or mag. I don't think it's an issue in soil? cal/mag in water is probably not even usable by the plants so I would continue with your regular regimen unless you see problems. Otherwise the instructions on the bottom should suffice (5-10ml per gallon in hydro, mine says.)

 

[habeeb]

believe it's 5ml a gallon people use, but that's for lucas formula

what nutes are you using, so people have a better idea how much cal / mag you already have in your system

 

[MHHSP]

Using foxfarm grow big no Ca listed .6% Mg main veg fert, typically every other water with liquid karma no listed Ca or Mg and earth juice micro-blast no listed Ca .5% Mg.
Just to clarify on the medium it is a soilless mix, sunshine mix #4. I do mix in dolomite lime at 1.5 tablespoons per gallon mix to help buffer pH and add a little Ca and Mg.

 

[mdk ktm]

I just recently got a cal def on seedlings that i put in soil. It surprised the shit out of me. With RO, I always use 5ML/gallon of cal-mag or magical in hydro, and now in soil.

 

[stony2]

mix it back with 1/3 regular water, and you'll be fine

 

[MHHSP]

My only water available for the winter months is salt softened water so I would not mix that back in with any ratio.

 

[MHHSP]

So does 5 mL per gallon with every watering sound ok? Or should I not give it when I feed, maybe like every other watering?

Any other products that you guys would recommend for supplying Ca and Mg in irrigation water? Don't really care for the 2% N in calmag + but I think it is a good product.

 

[mdk ktm]

I put it in there every watering. And every time I add back to my rez.

and I have heard that advanced nutrients has some good cal-mag, but I don't have experience using it. I think the advanced has more micro nutes....

 

[acellular]

I calibrated my ppm and p.h. meter today and did a test on 0ppm r.o. water and got:
Fulvex at 3ml./gal. = 40ppm
CalMag+ at 3ml./gl. = 135ppm.
Fuvex and CalMag+ at 3 ml./gallon each = 175ppm
P.H. at 4.5 after adding Fulvex and CalMag+
6 drops of P.H. up from Botanicare brought P.H. to 7.2
PPM went from 175 to 183 after adding P.H. up.

 

[TheCleanGame]

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