Main Cabinet Evolution

Did a final res-change a few days ago, went to the final nute ratio on the schedule & am running at around 275 ppm after addback, & it moves to around 325 before the next addback. pH has been wanting to rise after the res change, so I’ve been adjusting it down after addback to around 6.0 - 6.1.
I’ve also been tinkering with my humidity controller & heater settings, lowering RH & temps a little bit. I lowered the heater target by 1f lights on & lights off, trying to keep the lights-on high air temps at the tallest tops to 88f or below, & lowering lights-off temps slightly.
I also raised the light another inch, lowering ppfd by around 150.
I reduced the humidity main target & the humidify & dehumidify differentials all by a percent.
Cab Ceiling:

Tallest tops:

Mid-height tops:

Shortest tops:

Under screen near heater:

Lung room ambient:

Picked up a 5-gallon 220 micron Bubble Bag to go with my old 1-gallon kit, to make processing all of this seedy bud a lot easier:

Put together a Jardin DP-90 to use as a drying cab. Could also be used in place of my current clone cab:

Made a swing gauge for the exhaust port…

…& recorded some flow data:

Far-red puck arrived from RapidLED, although I won’t be using it until next time. The output voltage of the power supply is different as compared to the UVA puck, so after I took the pic I wrapped some red tape around the barrel connector.

Wide spot lenses:


Trying to knock down some temp spikes. I’m not entirely sure why the air temps tend to spike up at the beginning & the end of lights-on, but the weather has been warmer for the past couple days & my air temp fan sensor needs some dialed. I’m still running the box in ‘humidity priority’ mode, but I turned down the exhaust fan air temp sensor control so it would turn on at a lower temp than 90f at the tallest tops. I also raised the sensor itself a little bit. Last night after I adjusted it, it started venting at 89.4f a couple times by the end of lights-on as indicated by the couple of spikes down in RH. I turned it down a little more tonight & it tripped at 87.6 at the tallest tops, so I left it there for now & will watch where the air temps & leaf temps max out at. Usually I’ve been seeing at least a -10f leaf temp offset anywhere on the plant, although that will tighten up as the leaves fade out & stop transpiring. The anti-humidity fan was already holding the box down at around 86f at the tallest tops tonight, but it is humid out & the anti-humidity fan is running more/longer & keeping the temps down anyway. I had to unplug the anti-humidity fan & let the humidity run up in order to run the temp up so I could set/ check the air temp sensor setting again tonight. Last night was warm & drier, & that helped to run the box temp up on its own. The weather has been flip-flopping warm & cold, wet & dry.

The leaves are starting to fade from the top down, & the tallest tops are looking a little dry. PPM has stabilized at around 275ppm before & after addback. pH has been swinging a little bit, it started to head down again, & I’ve been adjusting after addback.

Chop should be within the next couple days, but I’d like to see how the air temp & RH end up after making the adjustment to the air temp sensor first.


Had to tinker with the air temp exhaust fan sensor settings some more, but got it to smooth out at 85f max at the tallest tops. I also raised my RH target 1% on the humidity controller to help the RH keep up with the stronger fan.

Thing is starting to plop over on itself mostly on the left side, & I have my newest data that I wanted, so I’m probably going to chop it very soon.


Chop chop…

No issues with the roots.
Had to throw out the net-pot since they tore it up.

Other side:

Cross-section from below where the net-pot had been:

Loaded the stalks into the drying tent.
I’ll have to find a better spot for the RH controller:

Thermpro readout from the drying tent:

Main cab will be undergoing some minor upkeep & improvements over the next few days, to be ready in time for the next plant.


This was an awesome run to follow. :pray: thanks for putting in the time to do it. Congrats on the chop.

1 Like

Thank you, I’m glad that you’ve been enjoying everything.

I’ve been doing some maintenance & have mostly finished.

‘Done!’ Checklist:
-Replaced carbon in small filter, washed dust-cover.
-Installed timer for Far-Red puck.
-Installed/ matched light hanger sets.
-Installed high oscillating fan mounts.
-Removed 250w door heater, installed 100w heaters on door & rear wall.
-Removed old outlet & wiring.
-Relocated & installed new box & 15A outlet, wiring, & breaker.
-Caulked, spot-primed, painted affected areas.

I still have a short list of a couple things to do such as making mounts for the pucks, but it’s nearly ready to go.

Here the work was mostly done, & I was about to start re-hanging the wiring harnesses.
Here’s how they were during the work:

Top & front harnesses stowed out of the way during maintenance:

Mostly sorted:

I had to pigtail one timer over the other so it would fit on the power strip. The timers will be running my UV & Far Red pucks. The strip also powers the 4" circulation fan hanging nearby:

Did a little more work on organizing the wires:

Rear hanger & power cable stowed for Kind X220:

Some wires need to move if the light moves, so they have double-sided velcro wrapped around them & are stuck to the outside of the velcro wrap behind them.

Test-fitting all of my crap. I still need to install some wiring loom & zip-ties to go across the front of the screen. Also I should install another insulation barrier for the back-side of the bucket:

Here’s what the cab did overnight on a fairly cold night with no power going to it, just to see what I’m working against. The door was open until a little after 3am:


I Installed a heat shield between the rear heater & the bucket.
I moved the air pump to the left side of the bucket, closer to the front:

Installed the Kind to get ready for a plant.
Also reduced the size of the front heat shield.

Heaters will be doing a shake-down run tonight. I have the heater controller set to target 72f & to fall 3f before turning on again. Lights will be off, & the humidifier & exhaust fans will not be running. Oscillating fans will be running for a couple minutes every few minutes, & the 4" axial fan up top will be running constantly at around 40% power. I placed some Thermpros is spots where I want to see the temps.

1 Like

I had good results from running the heaters by themselves, so I brought the light online in 25% increments to see how much heat it added.

Thermpro (new dark-mode):
The wavy line at 72f is the heater alone, 25% light power brought it to 76f, 50% power to nearly 84f. Next I started setting the exhaust fan during the 75% & 100% light power settings.

I set the air-temp exhaust fan controller sensor to trigger at around 85-86f.

Then I set the light back to 50% power, & set the height to give me what should be around 300 PPFD at the top of a plant once I put one in there, filled the humidifier & set the controller, & I’ll see where it all ends up tomorrow.

Drying cab progress:

DryCab Thermpro today:

DryCab Thermpro for the week:

Stems should be snapping soon.
It’s all going to hash anyway, but I gave it more of a slow-dry & let the leaves gas out slowly anyway to test out the new cab for such things.

1 Like

Bunch of Thermpros after doing some testing & adjusting:

Here are the results after introducing the humidifier & RH controls last night. Neither exhaust fan activated after that point. The air temp exhaust fan is set high as an emergency exhaust. The ‘anti-humidity’ fan is set to exhaust at 5% above the RH target, & it didn’t hit it. This is fine for now because it gives me a baseline of what the temps are doing without exhausting. For now I’m mainly looking for even readings above the heaters at screen level, & at the bucket lid.

(Light was at 50% power. Heaters target was set at 73f, & I don’t think that the heaters were coming on much if at all.)

Cab ceiling:

Thermpro on right wall of cab between light & screen:

Screen-level, above rear heater:

On top of bucket lid:

Screen-level, above front heater:

Lung-room ambient:

After that, I wanted to see where I needed to set the heaters in order to have them start adding temp. First I added 5f to the heater target,
& that added maybe one degree f to the air temps.
I’ll use the Thermpro from the bucket lid to illustrate the next few steps:

It got up to 82.6f when I added 5f to the heater target:

It got up to 85f nearly 86f when I added another 5f to the heater target. Heater target was 83f & offset was 2f.

Then I double & triple-checked my air temp exhaust fan settings by cranking the light to 100%. I disco’ed the humidifier during these tests. Air temp exhaust fan is set to dump at around 86 to 87f.

Finally I turned the light back down to 50%, turned the humidifier back on, & let it shed all of that heat-soak & settle down around 82 to 84f. This should be a good starting-point for the next plant. Right now the anti-humidity fan still doesn’t want to vent, but once I get water in the bucket & a plant growing in there, it will eventually start to push the RH up enough for the anti-humidity fan to vent the box. I can also adjust the settings on the RH controller if necessary.

1 Like

Took too long to edit above, but going over the readouts & thinking about exactly what I did & wanting to keep this straight for reference, I think I actually turned the heater target up 6f (not 5f), to 84f here:

…& then I turned it down 1f to 83f for the final adjustment before buttoning it up for the night:

Also, one other adjustment I made at that point was to lower the oscillating fans on-time from 2 minutes to 45 seconds, & the off-time from 3 minutes to 2’30".

1 Like

Still making a few more observations & adjustments before planting anything yet. Probably will be ready to drop something in by tomorrow.


I wanted to see how often the heater was actually running, so I put a Thermpro right on one of the heaters.

On-heater Thermpro:
From around 2pm to around 5 pm it was warm enough for the heater to turn off. The shallow spikes earlier are the heater maintaining target. The really big spikes seem to occur after I open the door to do work, & it has to recover. Usually I turn the heaters off when I open the doors so they don’t just sit there baking. But they will still run up after turning them back on right before closing the door if the cab has cooled off. The heater plates heat up quickly & hold a lot of heat for a long time once they start cycling though. Ignore the RH readings from this one.

I also added a full running bucket yesterday, but it didn’t affect RH. The cab still was not venting RH much at all, so I wanted to dial that in today. I would also be able to compare how the heater runs with more venting going on.

Bucket lid Thermpro:
From 1:40am thru around 5pm the cab was running without venting more than once, or maybe twice. Then I started tuning the RH controller until about midnight. I raised the target RH from 65% to 68%, I lowered the dehumidify target from +5% to +2%, & I raised the humidify target from -3% to -2%. I also moved the RH sensor lower to just below the screen. I made the last adjustments a couple hours ago & it seems to be settling down & only venting for a few seconds occasionally. I’ll let it run thru tomorrow to see if it needs any more adjustments anywhere.

Lung-room ambient:

1 Like

I made some final settings & adjustments before planting. I reduced the heater temp target 1f, & tightened the humidify & dehumidify offsets to -1% & +1.5%, respectively. Tightening the RH offsets seemed to solve an issue with the RH not hitting the dehumidify target after a while, & the heat building up to around 86f. It stabilized before the heat exhaust fan kicked on, but I can get more stable results with the tighter offsets. This should become a non-issue once the plant is big enough to transpire more water.


Cab ceiling:

Bucket lid:

Above rear heater, screen-level: (Slightly higher temps & lower RH as compared to the sensor above the front heater.)

Above front heater, screen-level:

On front heater:

Lung room ambient:

I tapped away the lava rocks, untangled the roots, & did not prune them:

Into the bucket last night:

Last night:

A little droopy after 24 hours, we will see what it does:

Another from tonight:


Growing a bit:

Leaves are stressing due to the transplant & the new environment. By tonight the RH couldn’t hit the ‘dehumidify’ target again, despite my tightening of the RH offsets a couple nights ago, & the air temps started to climb. Leaf temps are still reading around 10f lower than air temps when I checked them today. I keep forgetting to check PPFD, but it should be around 300 at the top.

Bucket-lid Thermpro last night:

Bucket-lid Thermpro tonight: Shows the condition where RH wasn’t climbing high enough to get the humidity fan to dump, & temps started to climb. Temp might have eventually risen enough for the air temp exhaust fan to take care of it, but it was time for me to open the door & check on the plant anyway. This should not be an issue once the plant gets a little bigger & transpires more water.


Topped & trained, eight main nodes, female pre-flowers identified on the topped portion. The wire near the topped area is helping to push the top down, & the other three wires are pulling fan-leaves up.

I’ve been lowering target RH, & transpiration has been rising, & I’ll be raising the 225 PPM through add-back over the next few days.
pH has been 6.1 -6.3 the past few days, & I moved it down to 5.8 - 5.9 after add-back today.

(Leaf temps are running about 10f lower than surrounding air temps/ Leaf-temperature offset is around -10f.)

Leaf VPD Calculator


Screen-level over rear heater: (The sensor over the front heater is similar with lower temps & higher RH.)

Sensor on heater: (Ignore RH)

Lung-room ambient:


Ran this through my bubble bags:

Left column is the first run. 160u mesh at the top, 73 in the middle, 25 at the bottom. Checking with my 30x & I Think that the 73 is the cleanest in terms of plant material, but not sure which has the most caps. Probably either the 73 or the 160.

Ramped up the RH & did a lot of defoliating:

Started to train the mains across the screen:

Another RH increase & a root-prune will probably happen tomorrow, & the res is also due for a change.

1 Like

Pruned the roots a week ago & swapped the res solution. I raised the RH & ended up having warmer weather & a couple temp spikes during the following couple days which I couldn’t iron out through the RH controller alone. A quick adjustment to my air temp exhaust fan sensor put things back in check, although the RH drops more whenever the air temp fan activates. It’s a more powerful fan, & also the sensor takes a little longer to react as compared to the RH fan & sensor. I also dropped my heater target by 2f.

Root growth as of yesterday:

Pruned some more from under the screen:

The leaves are showing some deficiencies due to cannibalization after the root-pruning, & also due to the PPMs getting a little low. But they’ve stayed plump with moisture for the most part. I’ll be raising the PPMs & dropping the RH back down over the next few days. Looks like I ended up putting this one too far to the left now. Oh well. I’ll probably pull one or two of the tops from the middle over to the right so the left side will get less loaded up.

Thermpro, screen-level above rear heater: Leaf temps are temporarily running closer to air temps due to reduced transpiration mostly as a result of the root pruning, & also due to the increased RH. Instead of around -10f, I’m seeing closer to -5f.


Flipped to flowering last night, after mounting my far-red puck:

Also installed the flood lenses onto the LEDs of the puck, which is timed to run for ten minutes as soon as the main light turns off. I’m going to try running the main light on a 14/10 schedule, at least until the last couple weeks of flowering where I’ll probably go back to 12/12. For now the main light is at 50% power on both channels, & the plant should be averaging 25 DLI across the canopy.

Training, pruning, & defoliating:

Still increasing PPM & on “week4” ratio, but not adding Superthrive to the add-back mix since I am going into flowering. Wondering if I should stick with “week4” nute ratios through the first two weeks of the flip like I have been doing, since I am now running a lighting program which may hasten flowering. I might move to week1 flowering ratios a week earlier than I have been.

Roots last night:

Adjusted the heater controller onboard timer & setpoints to run with the flip.

Also I placed an external timer on the RH controller outlet to prevent the humidifier from receiving power during lights-off.

1 Like

More pruning & defoliating:

Plant seems to be responding better to the twin heaters vs. the larger one. It seems to be stretching more evenly across the front & back edges. However the corners aren’t even right now, due to how they trained out. The back right corner is a little behind the other three. I’ve gotten the PPMs up to around 475 after add-back today, & probably getting pretty close to where it should be for now. pH has been around 5.9 to 6.1 .

Leaf temps are back to running around 10f under air temps, plant is drinking about a half-gallon a day.

Cab ceiling:

Canopy top: (Zoomed in because it has only been in place for a few hours so far, relocated from the bucket-lid.)

Screen-level, above rear heater:

Screen-level, above front heater:

On heater:

Lung-room ambient:

1 Like

Main Cab update:

I decided to mostly abandon my 14/10 plus 10 minutes of far-red at the beginning of the dark-period flowering experiment. After nearly two weeks of running that schedule, I got a lot of stretch & no signs of flowering.
So I bent everything over & tied the tops, & switched back to 12/12.

I also ramped in the far-red at the beginning of the dark period by not giving it any for the first night, then one minute the second night, two minutes the third night, & then three minutes at the beginning of each night for the next ten days. After the third or fourth day, I was seeing signs of flowering. For my next run I will try 13/11, & ramping in the FR again, instead of just going right to a set period of ‘max’ time with it. I think the plant wants to see a ‘daily’ reduction in pfr at the end of the night in order to start flowering, so I don’t want to get all of it to totally convert by the end of the first night.

However, the plant was basically at the beginning of flowering, & still had its three weeks of stretch to put in. I turned the far red down to two minutes at the beginning of each night after a couple weeks.

At some point I engaged the Photontek, & I also made an aluminum mount for my UV puck. It runs for eight hours, turning on two hours after the main light turns on:

Here are the FR & UV pucks placed on the Photontek:

I had to raise the light to near max height to keep up with the stretch, & it’s closer than I would like. The tallest buds are probably in at least 1500ppfd, maybe more. I haven’t checked lately. Also the pucks are more like spot lights at this close distance. They really want to be at least a couple feet away from the canopy, but I’m still running them anyway.

Another pic from today, I think I’m at day 37 from when I went to 12/12: The canopy is much more even after having gone to the twin heaters this time.

No signs of hermies yet. Nice white pistils starting to retract into the calyxes:

There are a lot of larfy buds underneath, but they have a lot of frost on them:

Here’s the Thermpro readout from around the same level as tallest bud. The actual bud temps of the buds closest to the light are running at around 75f-78f, & the big fan leaves across the top of the canopy are around 70f-73f. The plant has been transpiring about 3/4 a gallon of water a day. The heaters are usually not running anymore. Unfortunately my low RH will be going bye-bye soon, as the season continues to change.

1 Like

Main Cab update:

Hit a couple minor bumps this week, but the plant seems mostly unaffected. Had the pH crash overnight about a week ago. I’d been trying to get ten days out of a bucket, got nine by maintaining pH with pH up for the last couple until it crashed down to around 4.5 overnight. Did a full res swap.
When I did the res swap, I shut off the switched power on my strip to shut the res pumps off, & I accidentally let the door shut which let the cab heat up for about half an hour, because my vent fan controllers are also on the switched plugs. A few days later (yesterday), & I realized that I was about a week behind on my 12/12 day-count & nute schedule.
I’m finishing up week six now from flip, & should have switched to the ‘late bloom’ ratio & cut my PPM this week, & I’m addressing it now.

I also raised the light slightly. PPFD at the top of the tallest bud is around 1400, & 900 to 1000 across most of the rest of the canopy. This is not accounting for any UV or far-red photons, since my meter does not read them.
Once the air temps get up to around 85f, the bud temps of the tallest buds are around 78f. Leaf temps are around 70f across the canopy. Lights-off leaf temps were about 1f below ambient when I checked the other day.

Thermpro, even with tallest bud:
Air temps dropped a little after raising the light last night. RH also dropped along with it, not sure where that will end up tomorrow.
RH also spiked during lights-off, although I can control that a little better if I periodically run my whole-house fan to vent the house, provided that the outside ambient conditions would allow for an improvement.

No signs of hermies or pollination. Pretty sure my problems from the last two grows were strain-related then.

Buds are starting to get denser.

Some of the taller & larger fan leaves have been fading more quickly than the others, even with ample PPMs over the past couple weeks. They are getting a lot of light, but raising the light might help, although they are still getting a lot of light. I also swapped the pucks around so the UV puck won’t be shining so much on the taller areas. Not going to worry about it too much, as it is time for them to start fading anyway.

1 Like