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Few questions about rootzone analysis by 1:1.5 extraction method.

Firstly I would like to say that I have compared the results of the same mix by measuring right after mixing it together vs putting it back together and waiting for 2 hours before taking the measurements. It read only 20 ppm more later and ph was exactly the same, so basically in my experience it's not worth waiting at all. I just make sure that it's well mixed and I squeeze every bit of water out of it.

Secondly I would like to ask what is the best timing for taking the sample from the rootzone? I figured it's just before watering. Does it make sense?

And for the last thing I'd like to ask what is the point of adding water to coco to get it to field capacity before mixing it into water (in case if it's too dry) ? Why not just add coco until the slurry mix hits 250ml mark whatever the moisture? I find it really hard to understand the reason behind step 2. The moisture content of coco changes its volume so slightly that it's barely noticeble. Is it really about such accuracy?

One more thing, is it important to measure ph before filtering coco out of the mix and EC after filtering? I tried both ways again and got same results. What is up with that?

Here's the method:

1)Take a sample of CANNA COCO from the slabs or pots. This can be done with a soil core sampler or a trowel. To get a representative sample the coco must be collected from as many places as possible.
2)Collect the sample in a bowl and determine whether it contains the right amount of moisture. The coco has the right amount of moisture if moisture disappears between your fingers when you squeeze it. Add demineralised water if necessary and mix the coco.
3)Take a 250 ml measuring jug and fill it with 150 ml of demineralised water. Add coco to the 250 ml mark. Fully mix and allow the slurry to settle for at least two hours.
4)Mix again and measure the pH.
5)Filter this material and measure the EC.
 
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