Where do you get 3.2 from?
First time running full strength. I figured because I wasn't seeing any nute burn and that the ec kept dropping that it was still hungry and wanted more.
I am growing in 16 gallon totes using 5 gallon mixtures. I ph to 5.8 and let it rise. The next day it's like 6.3 and I then ph daily to 6.0. she's on an every 3 day res change now. I let it go down to about 2 gallons.
I grown in an unfinished basement. The only thing I can control (somewhat) is the humidity.
PPM of 1600 (500 scale) is EC 3.2
Plants don't get "hungry". Some nurtients are brought in because to balance the electrical charge of what the plant is exuding but the other 50% of nutrients are taken up due to transpiration. If you keep adding more nutrients, those chemicals will be taken up and will, eventually, damage your plant.
EC is
not an indicator of nutrient strength - it's a measure of electrical conductivity and changes when only a small number of nutrients are removed from solution.
If water is being taken up, chemicals are being taken up. N, P, and K are taken up very quickly (hours) and have little/no impact on EC when they're removed from solution. If you keep adding more chemicals, the plant has to take them up because of transpiration and the best you can hope for is to have a plant that's staggering along, just this side of toxicity.
The reason to put nutrients in the root zone is to allow the plant to take up nutrients at the sufficiency level. Once you've done that, that's all the plant needs to reach its genetic potential. Adding more nutrients simply puts more chemicals in your plants, costs more money, does not help the plant grow faster or bigger, and will, eventually, lead to toxicity resulting in a nutrient burn or imbalance.
The rise in pH is completely normal and it just a function of nutrients being absorbed. Conventional wisdom is that "optimal" pH is 5.8. but, in a recent video, Bugbee recommended 6.0. One fun fact is that, if you search for pictures of charts that show how nutrients are taken up at different pH ranges, there's a lot of different opinions on what is taken up at what pH. It's surprising how much variance there is.
I got a good price on a Bluelab doser so I set it at 6 and don't muck with it but, as I continue to learn more about growing, the picture I'm getting is that, as long as you stay above 5.5, it's really OK to have pH varying up to, say, 6.5 (hydro).
16 gallon totes is a good size but you're replacing 2 gallons in 3 days? That's a lot.
Re, swapping the res - that's a lot of work and there are a couple of different methods of topping off which will save you labor and $$. I'll post some papers and notes, if you're interested.
"I grown in an unfinished basement. The only thing I can control (somewhat) is the humidity."
I'm in an unfinished garage but it's in Southern California, about 10 miles from the ocean and in a tiny little area of a few square miles of the Mediterranean Warm Summer climate. That gives me temps of 70-80'ish but RH is 80-40 so it takes some hardware to "influence" the grow environment.
