I'm being very honest with you when I say this... you're going to have a hard time getting those plants to recover enough to stay healthy through a full flowering cycle of 2+ months. I would personally chalk it up as a loss and start over.
If you decide against that, then here's what I'd personally do if I was determined to flower them out.
- Leach the salts with a heavy water of plain PH'd water. Clear runoff is the goal here. It may take quite a bit of water for 10 gallon pots.
- After achieving clear runoff, mix up 5 gallons of water & nutrients at 1/4 - 1/2 strength and water in.
- Nutrients should consist of 50/50 base nutrients and a calmag supplement. 400-600 PPM would be ideal.
- Immediately after re-feeding the soil, transplant into 20 gallon pots. Ensure you're using high quality soil.
- Now wait and watch.
Moving forward I would advise watering to achieve runoff every time. It's easy to get pockets in the soil and get salt buildups when you do light waterings with zero runoff. Also ensure you're using a solid water source.
You have a lot of problems going on with those plants. I'm not saying this with rude intentions either, just stating the facts. You'll need to avoid doing what you've been doing to ensure you don't have these problems in the future.
When the rhizosphere is not balanced or healthy it creates lockouts in the plants and that's what I see in your plants. It's not just one thing, it's quite a few symptoms. As soon as those imbalanced are rebalanced, you'll notice healthy growth again. It's definitely going to take some time since those are not young plants.
One last thing, not sure if you've used microbes before but I highly recommend them. I personally use recharge but there are others on the market. You WANT beneficial bacteria and microbes in the soil to help breakdown nutrients and make food more bioavailable for the plant to eat. Microbes significantly help nutrient uptake even when ph levels aren't ideal.
edit: I don't see anything humidity related. FWIW, I personally aim for 50%-70% during veg and 45%-55% during flower.
