TDS and EC readings Help....

hey guys still fairly new to all of this i just installed a constant monitor TDS meter in my system today did a fresh flush and fresh round of nutes, Bas water was reading about 170 ppm, i have a EBB flood system with 45 gal total water i added, 225 ml of Ionic Bloom, 34tsp. of Ionic Boost, and Greenfuse Bloom Stimulator. My ph is holding at 5.8 right this sec with no adjustments but my TDS readings are only showing 500- 440ppm, and acording to the Ionic schedual i should be around a 1.8 EC which should be around 900ppm. What should i do stick with keeping my tds in the 500-440 range since i know that was a full and acurate dose or should i add more nutes and reach for my target TDS reading ??? Also i do not have a EC meter so i can not take an actual EC reading..... What do u guys think ??

Is your ppm meter calibrated? Do you have an electronic ballast near your ppm meter? Try shutting off your lights and see if the ppm meter changes. "There could be electrical noise" being created by your ballast that is causing a miscalculation. If the reading does not change when you shut your lights off then this is not the problem. After checking that, I would test the ppm of bottled water. Let the meter sit in the water to adjust to the temperature (5-10 min). The bottled water should have a ppm around 0-50, this will tell you if your meter is calibrated. I would take it a step further and purchase some calibration solution just to make sure everything is dialed in.