I was reading this thread as I too was having the same problem with my first grow in a new sealed room. This is the first time I have tried a sealed room with organic fertilizers and bennies. I started my seeds before I was finished with the veg and floor rooms. I am growing in soil and I am trying to use the
Earth Juice products as described in "Finding My Nutes". The room in which I started my plants from seeds will be my drying room so it is relatively small 4’ x6’ x 9’ tall with a 400 watt MH light. I had no ventilation or heating, so I hung clear plastic over the door opening as it was cold outside and I wanted to keep the temp up to growing temps.
It has taken me longer then I planned to get the veg and flower rooms setup and the plants grew in 1 gallon containers for almost 2 months in the drying room. I went into the room everyday sometime more often to monitor the plants. The plants started showing the same signs of yellowing of the leaves as you described.
When I got the flower room (9’ x 20’ x 9’) setup to the point I could move the plants, I transplanted them into 5 gallon pots and put the under a 1000 watt MH light. The air conditioning and the CO2 was not setup and I did not have the door on the room. The plants did not recover. They would grow new fan leaves that would turn yellow very soon after starting to grow. I was venting the room through the door.
I thought the problem was magnesium deficiency and so I tried spraying with a mild solution of Epson salts which did not help. I then decided that it might be a nitrogen deficiency as the nitrogen in the
earth juice products is low. As I was desperate at this point I added an inorganic fertilizer that was 20-20-20. I also got my co2 bottle and regulator setup at about the same time. The plants perked up within a week, but since I changed 2 variables together by adding the CO2 and inorganic fertilizer I am not sure which one had the positive effect.
I do not have much plastic or vinyl in the room other then pots, and water buckets.
I have been in flower state with HPS lighting (a 1000 watt and a 600 watt) on 12/12 for the last 2 weeks. The room is sealed with CO2 injected every 2 hours. I monitor and ajust the temp and humitity manually and sometmes leave the room open to reduce temps.
The plants are doing much better. The white widows, blueberry, purple kush, northern light and sweet god are looking good with nice starts to the buds. The jack herers are not as far along but they have a lot longer flowering.
Not sure if this helps but since you seem to have the CO2, temps, ph and tds dialed in I have to wonder if it is a nutrient deficiency.