That's a strange-looking plant. I've only ever worked with indica dom strains. Is that a normal growth pattern for a sativa? I always say I want to try growing a sativa sometime, but not that, lol.
I don't want to knock something I haven't tried, but why do people use those fancy cloners? I get 9/10 with rapid rooters and clonex. I don't cover them or do anything other than make sure they don't dry out. My temps in the veg closet are frequently around 81 82 during this time of year.
I've never heard of getting moldy leaves, just moldy bud late in flower. Is your room very humid? Or perhaps all the foliar feeding you're doing is causing the mold?
Fungus gnats are more of nuisance than a real problem unless you let them get way out of hand. bobtokes is right, they only eat the roots and can usually only kill seedlings or clones. You can just buy some mosquito dunks, crumble a bit up and sprinkle a bit into the top of your pots. They'll...
I recently went through this with some 2+ year old seeds. I kept them in a dark dry place but I suspect that exposed to some heat in the 90s to 100s at some point. I must have gone through 200 seeds before I got 3 to actually grow into full size plants. The only way I got any of these to...
In my experience, you can change the light schedule however you want and it doesn't shock the plants. I've accidentally left the lights on all night during flower a couple of times (I don't recommend this) and had no ill effects. Maybe it's just the strain I grow, but all this extra hoopla...
I wouldn't scrog on my first grow. KISS. I use tomato cages and/or bamboo pools. Chris323 is right about the height doubling. The key for me would be do you think your roots are fully developed? If so, flip now or when the plants get to 1/2 the max height you can support in your space...
If you're running coco, I'd do a flush with 1 tsp vinegar, 1 tsp molasses, and 1 tsp epsom per gallon and then start feeding with every watering after that with a good organic fert like GO Bloom and CaMg+.
You could also put your HPS on it's own fan and ducting using outside air to cool and sending it right back outside without filtering. I also did that for years when I was running HID. The less air you have to move through that carbon filter the better.
Depending on the actual power draw and quality of those LEDs, I don't see them covering 48 sq ft in flower well. What kind of lights are they? I'm using 800w of actual power draw to cover 2.5 x 6.5 which is a third of your area. You might need a 4th 600w light which would probably fit the...