Why, the plants are growing perfect. I could run 10 gallons through and it will still be 1000ppm or more. Should run 100 gallons through?
Do what you feel works then. Some Cannabis can suck up surprising amounts of nutrients.
But i have found after growing one plant to the best potential i can in a row one after another fed and trained and adjusted and harvested individually. Spaced out to harvest a plant or two every couple weeks or less and a ton of clones run through for side by side tests of many things. I have found that keeping plants in the 1.0-1.5 ec range max is all that is needed and gives best flavor, smell and potency. Just a little nute and moisture stress helps potency. And overfeeding is the worst thing i can do. It hurts flavor the most but potency as well.
This year i watched a video from Bruce Bugby at the university of utah cannabis grow lab and to my surprise he recommends the same range after tons of testing and consulting with other growers. And he is one of the smartest people on the planet about plants. He is the one doing the research on light frequency and is why far red is added to grow lights and helps design new light meters for Apogee.
So there is that. ;-)