Update.
So amazing watching the plants grow and change. The day count is now 79 just 6 days from last auto harvest. The topped plant looks very close and has already condensed the stems and has been stacking for weeks. Fade going on even with amendments.
The natural untopped plant is way behind. Just now starting to change pistle color and no calyxes visible. The fur pistles are much longer than the topped plant.
No service today other than light check and rotation of plants to even up the side light effects .
After the reduction in the tent hight last feeding I have noticed that per the settings for fans and lights the configuration change resulted in a temp drop of 1.1 degrees at canopy hight. I dropped the hight by 7 inches and this increases the volume of the tent allowing the warmest air to be 7 inches higher. I placed some temp cubes around and found the whole tent is mixing well from floor level to the tent top. With a cube shoved up into the extractor hose leading out of the tent reporting 81 degrees air moving out of the tent and 75 degrees 31 inches down at canopy top.
I had been worried as with modest lights I am at 75 but I am also at 75 with heat support. I plan on running just the 400 watt unit for 4 plants and I am not worrying about heat load now as I have another 6 inches of drop if I need it.
I find it amazing after a year and a half of growing and 2 tents I still learn different data points relating to physical properties of heat and humidity movement.
Got out some electric bills from the last 2 years. Kinda easy as the bill has a link to history. I can say with some numbers to back it up that the largest increase in electricity is due to my wife's medications for diabetes that make her hot all the time. We went from house at 74 AC on to 70 AC on and I even closed off unused rooms and the only room in the basement that has a vent open is the grow room.
I need a door at the top of the stairs to the basement to make any meaningful reduction in HVAC costs. My wife is vetoing this as honestly it is costing 50 bucks a month during the summer more for the increase in energy and the install of a door would mean boxing in a door frame as the stairway goes to the ceiling and I am unable to do stuff like this anymore.
But there is this.
Hmmm
tape measure!