Bagged Coco question

[Doubledealing72]

I buy the mother Earth coco that's bagged and ready to use.

I've noticed that when I first open the bag, the runoff pH comes out pretty much at what I put in (put pH water of 6.0, runoff measures at 6.0).

If I use a bag I opened a few months ago, my runoff when I first wet it down is somewhere around 4.3-4.8.

It takes me somewhere around 20 gallons of water to get my runoff up to 6.0, and that's not even pHing my water (comes out of the tap at 8.8). Once I have it at 6.0, I'll throw a few gallons of 6.0 in. This way I hopefully get all of the 8.8 water out of there. Then I plant my rapid rooter in there.

This is a multiple hour process, and just a pain in the butt to start a grow. I have read that reading the runoff in coco is not needed, but I feel like there is some chemistry going on that is above my head.


This time around I had 2 pots to fill using old coco. The first one I did the 20+ gallon flush. The second one I treated like a brick of coco. I put it in a fabric pot, and put that in a 5g bucket which I filled with pH 6.0 water. I then waited about 5 hours before I checked on it, and it came out about 5.4.

Is there a better way to do this? Do i need to worry about runoff? DrPhoton , what do you think?

[DrPhoton]

I believe that you do not have to worry about run off. Doing so and trying to correct for runoff can cause a headach and further problems. The ph in the solution when in the media, will naturally shift with the interaction of the media, water volume shifts, nutrient ratio shifts etc. Its unavoidable unless you increase your fertigation rate or use DWH. What is most important, is making sure your inflow PH is correct so it is in the optimal range imediatly when given to your plants.

[DrPhoton]

Deep water culture.

[Iammygod]

@DrPhoton
"so and trying to correct for runoff can cause a headach and further problem."


Can you explain please?

[DrPhoton]

If the run off PH has deviated from the inflow PH. Trying to correct, by changing the inflow PH could cause wild fluctiations of the PH in the media. Causing further problems in ph stability and nitrient lockouts.

[Iammygod]

Coco categorize as moderate CEC substrate. So as coco is able to retain and release elements, The pH and EC of the runoff water generally deviates from the actual root situation. The most reliable method for measuring the nutrient levels and ph in coco is using the 1:1.5 extraction method. I run this method before planting and repotting. If you use electronic pen to measure ph, make sure it is calibrated as calibration is the must important.