Do not cut out Nitrogen during flowering..
Nitrogen is to a Plant is Protein.
Humans eat Protein, and convert it into Nitrogen. Plant skips this process, and takes up nitrogen.
Main thing is proper ratio, and dont over feed them. Improper ratio can also cause lockout of other chemicals.
Also at 33%, humidity is way to low.
But logically does it make sense to cut Protein, when you will be growing more, and producing more Biomass in the next couple months or so???
Say one has an 8 weeks flowering strain.
My base formula alol through the growth period is
19.5-20-39, and I adjust for PPM
Also added Epsom Salts.
I use 4-20-39 as base formula
then add
15.5-0-0 Calcium Nitrate
Then add Epsom Salts for Magnesium, and Sulfur.
I start seedlings out with 15% strength, but instead of 1 gallon water, I use it per 5 gallons, and feed, and water at each watering.
I also use Promix BX, and plants are grown from Seedling-Flowering under eather 1000w Hortilux HPS, or 1150w Gavita. Also Veg with a Gavita 1700e-1700umol LED.
We grow large plants because of plant counts, and bend them over to make more efficient use of the light, and dont top. Like plants that grow alot after flip, so veg period is less.
We usually veg 45-60 days, and then transplant into 20 gallon containers. Sometimes we may just Veg in 20g containers. If not we use 5g grow bags, and cut them off in the larger container.
But after flip, we keep the PPM on EVERY NUTRIENT going slightly UP every week, and at week 2.5- week 4 we will boost with 0-52-34. Monopotassium Phosphate, while all other nutrients are still Slightly increasing each week.
Then in week 5-6 Epsom Salts is boosted to supply more Mg, and Sulfur. Sulfur is very important for the production of Terpenes.
In weeks 7-8 PPM/Everything is reduced by 40%-60%.
Remember Nitrogen is Protein, and the thing that matters is Ratio, and PPM. Give to much N, and not enough P-K, they may not want to flower.
I slowly up the PPM of EVERYTHING each week, and also uppot as they fill the pot. I start in 32oz Deli Containers, Veg in 5 gallons