TDS vs EC

[GDub51]

I brew aerobic teas to fertilize my outdoor grow. When using rain water 50% mixed with aged tap water with a HIGH TDS of over 500 to get a water at about 250 ppm, I then add mycorrhizae powder, powdered bat guano, worm castings, kelp and fish extracts and black strap molasses in amounts about 1/4 recommended and wind up with a LOWER TDS than before!! How can this be? I have read that organic nutrients don't have the same EC as their salt based versions. Maybe they even lower the EC? I assume that my TDS meter is using EC and converting it for my "convenience" but is that the reason why the weird readings? I don't see any sign of nutrient burn. In fact since starting the "mini" tea brew for month old plants when they are only drinking a few cups a day, my grow looks better than ever! Deep green, three feet high and already with a "trunk" as thick as a pencil. (Girl Scout Cookies and Gorilla Bomb)

 

[oldskol4evr]

kind if have me stumped as to what your asking,might just be microbes ,i found this out when auqa man introduced me to hydrogard,when i add hydro gard to my feed the ppm drops almost to 3 something in a 33 gal can that is running at 6 ph and 1000 ppm ,soon as i add the beniftual ph drops,so i use this for the swing,i ph on the low side and let it rise when it swings past the limit or close i use the feed and hydro gard to top off,same with my coco grow i use it to drop the ph like a high dollar ph down in my mix,use it in soil also

 

[oldskol4evr]

also if that water been setting out for some time i shouldnt be 500 ppm ,if it is a little vit c or asorbic acid need to be put in it,the myco will also drop your ppm value

 

[GDub51]

Ascorbic acid can help neutralize chlorine but in so doing will not lower the dissolved solids content which is what I'm trying to control. My tap water does not drop in dissolved solids with aging, it will off-gas the chlorine. I'm trying to keep my feed water additives within the recommended parts per million of dissolved solids for each stage of life. Yet my TDS gauge has read lower PPM AFTER additives! That's what makes no sense to me unless it is because the organic nutrients I'm adding don't register or affect the electrical conductivity that most TDS meters actually use and then calculate to read out the PPM. So I take 550ppm aged tap water and mix with rain water at .5 ppm to get a base water of about 2 to 3 hundred ppm, then add nutrients and re-test and get an unchanged or even lower PPM! That's what I don't understand.