legallyflying
Well-Known Member
Ok people I am mystified. I am using an ebb/flood table that is 6' long and 2.5' wide. I've got about 100 liters of hydroton in it. It takes about 10-12 gallons of water to fill it to the point where it almost overflows. I keep 20 gallons in my rez. 6 plants in net cups in the table.
Now... When I fill the table with water and take PH readings in the water/hydroton I get 5.8 (my rez PH) on the downhill portion of the table (where the nutrients flow in), about 6.1 in the middle of the table and 7.1 !!!!! in the last foot or so of the table. (the upper part i.e. last to fill, first to drain). Or the life of me, I can't figure it out.
The water in this part of the table (upper) is quite a bit warmer than the other portions as when the water enters the table it is filling the lower portion first and I believe that as the water starts flowing tot he upper portion of the table its flowing through more hydroton that has been warmed to room temperature resulting in warm water.
So I thought that perhaps its the temperature of the water that is spiking ph and maybe I need a temp compensating meter. Did some reading however and the PH of a nutrient solution CHANGES with the temperature so it doesn't matter if your probe has temp compensation as it is reading the true PH. and to my dismay, with increasing temps, PH should go DOWN not up.
Any thoughts? are salts or something accumulating in the higher portions of my rez?
BTW. here is a very excellent article on PH ....
http://www.growersunderground.com/pH_Manifesto.pdf
Now... When I fill the table with water and take PH readings in the water/hydroton I get 5.8 (my rez PH) on the downhill portion of the table (where the nutrients flow in), about 6.1 in the middle of the table and 7.1 !!!!! in the last foot or so of the table. (the upper part i.e. last to fill, first to drain). Or the life of me, I can't figure it out.
The water in this part of the table (upper) is quite a bit warmer than the other portions as when the water enters the table it is filling the lower portion first and I believe that as the water starts flowing tot he upper portion of the table its flowing through more hydroton that has been warmed to room temperature resulting in warm water.
So I thought that perhaps its the temperature of the water that is spiking ph and maybe I need a temp compensating meter. Did some reading however and the PH of a nutrient solution CHANGES with the temperature so it doesn't matter if your probe has temp compensation as it is reading the true PH. and to my dismay, with increasing temps, PH should go DOWN not up.
Any thoughts? are salts or something accumulating in the higher portions of my rez?
BTW. here is a very excellent article on PH ....
http://www.growersunderground.com/pH_Manifesto.pdf