HYDRO Instrumentation

[Bigpapa]

Greetings fellow growers. For background, I’ve been growing in Hydro since 2016. My equipment has varied somewhat over time. I’ve done 600w M/H and HPS and LED. Right now I’m growing under 1 300w MarsHydro and 2 600w Roleadro COB LEDs in a 4 x 4 x 80 tent all properly ventilated with good air circulation. I do 1 plant at a time in DWC using GH Flora series nutrients. My results have been nothing short of spectacular with high yields and high end of range THC levels. And finally, I for the most part I grow photo-period strains.

I’ve spend a great deal of time closely monitoring PH and PPM levels. During my last few grows I’ve been pushing up the PPM with positive results. Now to the point. I started out only using a Hanna pen type PH meter. I also had been using a UBANTE TDS pen type tester for measuring PPM. When I started to want to use better instrumentation I moved up to a Blue Lab combo meter and everything was going well. My current grow is my first high CBD strain, Candida from Seedsman. I feed following the feed chart found here at GWE and typically start to slowly build up my nutrients at week 4 going from about 450 PPM to 750-800 by week 6 or 7. However, this plant started displaying nitrogen toxicity right after my week 4 water change which is when I started to recheck my nutrient solution. I found a wide difference in both PH and PPM readings taken at the same time using different instruments. Has anyone else ever experienced similar varying results from their instrumentation?

[alltatup]

Hi pops, If I understand you correctly, you push up the nutes during flowering. After week 4 or 5 of flower, I always begin to lower my nute quantities. I have also frequently seen nitrogen tox signs on leaves around week 4 of flower--one of the reasons why I stopped using Advanced Nutes. If I see the slightest sign of it in flower, I start to lower the MGB. And I flush.

As for your question: I only use a pH pen, which I replace about every two years.