I thought total dissolved solids on my meter were in ppm. I can read E.C. and TDS which is read in ppm on my meter.

I am using a Milwaukee 3 in 1 TDS/PH/EC meter but I calibrate for TDS because I have a lot of that buffer solution. My probe is the sm02 which can read PPM all the way to 4000.
JeffersonBud Reviewed by JeffersonBud on . advice please Lets get to the details for veg 3 100w CFL's running 6500k 1 small 6inch fan DWC system with 15 sites Milwaukee 3-1 ph/ec/tds meter 2 and 1/2 gal of RO water 2 6'inch airstones Rockwool cubes net baskett Rating: 5