Hey
I have both trimeter and a digital balast. I was told its the FR put off by the balast screws with the EC in the meter. I dont know what distance to use but my meter is mounted on the outside of my tent and I have the foil bubble wrap for heat protection. That kills my RF feedback. My meter and ballast are about 3-4 feet from each other and I have never had a problem.
Mine is with the readings. On all the forums they say never go above 1200PPM. i go off the botanicare labes and in veg Im at 1150ppm. I use RO water and everything. I use the 1000PPm solution to calibrate it. I just dont know why my readings are so high. My girls seem to be fine cause it was drooping the other day so i upped it to 2000 and it cause some burning so I went back to where its at. Its just fine now. I think it was the high temp I also think I had too much water in my DWC. How do you know what is too much. Im use to ebb and flow. FIrst time with a DWC keeping a mother alive. can any of you help?