water and ppm question

Discussion in 'Coco Coir' started by halfa380, Jul 7, 2011.

  1. how ya doing folks...........got a quick question.....my tap water is 60-70 ppm.before i put it to use, usually i let it sit for 24-48 hours.ppm does not change.when adding cal/mag to how many ppm i should aim for????before i start adding nutes?thanks in advance.
  2. Depends on the product you are using.

    With Botanicare Cal-Mag Plus every 1ml you add to a gallon of water will raise the EC by 0.1. This can be translated as 50ppm or 70ppm depending on the meter you have and the conversion rate it is using.

    I suggest at least 2ml but no more than 5ml. Your primary nutrient system should be doing the majority of the heavy lifting, the Cal-Mag plus is more for fine tuning.
  3. Thanks for reply...its 2 separate bags.its in the powder form. Cal/- N-11.6% Ca-16.6% and for mag/ MgO-16.2% S-13.5%.half a tea spoon of each in 5L jug is like 350 ppm.Is that too much/?or not enough?
  4. You should probably run them at a 2:1 ratio. Use 2tsp of the cal for every 1tsp of the mag and that should give you a better mixture to use. 350ppm for just the micro is a little high. You might actually be better off with 1tsp of the Cal and 1/2tsp of the Mag to get the right ratios at the right measurement.
  5. so youre saying i need more cal than mag?what about in flowering?
  6. #6 SCMC, Jul 7, 2011
    Last edited by a moderator: Jul 8, 2011
    What I try to do is keep my Calcium ppm around 80 to 100 for most of the grow. Maybe in the 5th week of flowering I'll cut back on the Ca. Magnesium I try to keep about 1/4 of the level of the potassium I am adding. When I'm cutting back on Calcium and increasing both Potassium and Magnesium levels after day 30, that's when they start to balance out. Up to that point it is probably better to keep the amount of Mg reasonable in roughly a 2:1 ratio with calcium and a 4:1 ratio with Potassium.

    Somewhere in there is the sweet spot for most plants.
  7. thanks dude

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