Ppm problems

Hi can any1 help im currently in week 2 of flower im using canna a+b, canna boost,canna cal-mag, rhizotonic and cannazym Im using exactly what they say to use on the schedual plus using tds3 meter for ppm reading but for some reason im not getting reading over 325 where i read its should be over 800 by now??

I grow in DWC (deep water culture) which is hydro and my plants like to feed at around 1050 ppm.

I feed in flood and drain at 1100 - 1150 without tip burn.

If you are using tap water and still only reading 325 the meter may be way off. Have you checked the calibration of your tds meter? You can also try your meter on distilled or RO water to get an idea of how accurate it is. Distilled water should be close to 0 ppm and RO under 10 ppm.