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Any ideas to organically leach calcium from soil?

My Calcium is through the roof. PH is fine between 5.9-6.8 between 6 rooms. EC is a little high( but is always high , might be an organic thing. NPK in all rooms are in range, but my mag is a little high too.I am thinking of a sulfric acid leach. Anyoe have any idears ?

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Try this: do a complete two-step flush with pH balanced water with an EC/PPM as close to 0 as possible. A two-step flush will happen just as the name implies: in two steps. Flush once through your medium to complete saturation. Wait ten minutes or so (use this time to roll one up), then flush again. This second flush will completely knock out excess nutrients and locked or undissolved salts (including high Ca and Mg content) you may have missed in the first flush.

I would suggest waiting for the medium to completely dry out before giving a healthy dose of fresh RO water (no nutes). I might also suggest lowering the EC of your nutrient solution a little to prevent this problem in the future. While we’re on the subject, what nutrients are you using?

The two step flush will be the most cost effective means to do fix your high Ca Mg levels. Hope this solves the problem!


great reply / advice to mwmzx6 for corrective action. He may also want to consider adding sulfuric acid to his water on a constant basis to help prevent this from reoccurring in a few weeks. Here in the upper Midwest we have alot of calcium in our water which is expressed in alkalinity levels of 275-300 ppm. We inject acid into our main waterlines to lower the Alk to the 80-120 part range depending on time of year.
I don’t recommend adding acid without knowing the baseline Alk and using a good test kit is important. We use the Hanna HIHI3811 kit and test our water twice a week.
If doing a one time or occasional application we will use 2-4 oz of sulfuric acid per 100 gallons of water, depending on how much we need to adjust.


I totally agree with davidm.msgs here! One point in particular that he mentioned was the baseline test. It would be immensely helpful for you to have a water analysis performed if you haven’t already. If you are on a city/municipal water source, the process can be as simple as going online or calling the water company for a water report. Federal law mandates that you as a consumer of local water have a right to access to these reports. If you are on well water you can have a water analysis performed by a reputable analysis company (some universities will offer these tests for a small fee).

Knowing your inputs is crucial to growing exceptional cannabis!


I just did a round of water and nutrient testing this last month. The dramatic change is in either the water or neuts …or both . I am taking samples tomorrow. Organics keeps me on my toes while turning my hair grey.Thank you for suggestions !

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