I don’t understand why people try and apply the chemistry of dealing with a water medium [hydroponics] with a compost or soil medium, the buffering in water are carbonates, to change it to a ph where all the dissolved nutrients are available to plant, means you have to reset the ph level to the best for water culture uptake.

Compost is made with a blend of acid and lime products to balance the compost PH level within a certain band ideal for most plants and keep it there.

Add water or a nutrient solution above or below that buffer point and the components slowly react until it brings the water in the saturated root ball back to the same point, this takes several hours, so the thing of I measured my run through, means absolutely nothing.

The horticultural industry produces hundreds of millions of plants every year, garden centres sell them, people take them home and grow them with no problem all using standard tap water.

Where I live depending on the time of the year my water varies between 7.6 and 8.4, I tested it for many years and my figures are very close to those published by my water board. I have never had a ph problem growing my cannabis or my vegetables, flowers etc, I have even reused my canna compost several times and not run into problems. It takes a very long time to alter soil or compost buffer levels.

Maybe if I lived in an area where the water board ph max/min bands were above ph 9 and if it caused a problem, I would not ph my water, its just to much faf, I would blend in a small percentage of ericaceous compost to my standard compost to lower the mixed compost buffer level a little.

Edit to add cannabis in soil or compost can take up nutrients in a much wider ph band than with hydro growing, you are in the hands of the compost makers as to where their buffer level is set.

Contributed by OT1

From HERE