2x2 RDWC #4: Test with Bag Seed

THCosmic · Jul 29, 2025

Hey everyone! This is my first grow diary and 4th RDWC grow in my 2x2 tent. I have a few years experience growing in soil before that.

So technically this is only my 2nd RDWC grow since the recirculating aspect was only added since the previous grow. Plain old DWC before that, but adjusting the solution was way too difficult without an external reservoir.

I currently have 4 plants growing, on day 10 in flowering. Being bag seeds, this will be the week I identify their sexes. One has already shown to be female, just waiting on the other 3.

New to this grow:
-6/2 light schedule for veg.
-Fixed up a minor water leak found in the previous grow.
-Upgraded the inline exhaust fans and added a dehumidifier to help maintain ideal temperature and humidity.

Now for some images to catch you all up on the grow:

June 24th: I started out with 8 and due to early PH issues 4 of them did not make it. I had to buy new PH pens since the ones I used were not calibrating correctly.
Germinated seeds went directly into the reservoir. They are all between 7 and 10 days at this point. No other growing medium is used. Using 1/4 strength nutrients.
The survivors make a backwards "L" before they are rearranged in the next images. None of the upper-left plants survived.

July 2nd: You can see the 4 I chose to keep. PH issues sorted out and the plants are recovering.

July 8th

July 10th

July 12th: After pruning, I decided to test whether or not I could get a clone to root if placed directly into the reservoir with the other plants. The test failed, as expected.
Also started LST to get the plants to take up more of the tent.

July 16th: LST continues. The plants are spreading out nicely. The plants are getting super bushy at this point. I did some major defoliation, the final one before flipping to flower.

July 17th: Decided to force the smallest to grow at a 90 degree angle to get it to cover more area. Flipping to flower soon.

July 19th: Final day of veg. Lights will now go to 12/12.

July 23rd: 4th day of flowering. Hard to tell the height on the bottom 2, but you can see the back 2 are shooting up for sure.

THCosmic · Jul 29, 2025

10th day of flowering. Upper-left plant is starting to show some pistils.

THCosmic · Jul 29, 2025

Image above is from 1am and I only noticed the 1 branch with pistils. 20 hours later I now see 4 branches with pistils. I am so happy that the largest plant is female! Hopefully the other plants start showing pistils soon.

THCosmic · Jul 29, 2025

10th day of flowering group photo:

THCosmic · Jul 31, 2025

Just got a digital microscope. Tested it out on a bunch of random stuff. Can't wait to try it out on the plants when the lights go back on. Will provide some more pictures of early flowering with it.

THCosmic · Jul 31, 2025

Took a lot of pictures with the new digital camera. Takes some getting used to and a steady hand. About half the photos were a blur, so I took multiple shots of the same nodes and chose the best image of each. Not even sure which plant is which in the photos except the one showing signs of flowering is definitely the largest plant.

Looks like a tiny pre-flower is starting to form on this one. Still can't be positive if it is female, but it does have more of a teardrop shape so I am hopeful.

Can't really see anything here, but was a nice clear image, hehe.

Not pre-flowers, just new growth for new branches.

Found a fiber stuck to this node.

Obvious pistils.

Long pistil coming up from the bottom in the center.

Need to get more practice with this microscope so I can get some better shots. Can't wait to start getting pictures of trichomes!

THCosmic · Aug 1, 2025

PH meters are a pain in the ass!

Get a solution sample from my reservoir. Remove PH pen from the storage solution. Dip and swirl PH pen in fresh RO water. Remove from RO water and lightly shake out as much water as possible, then pat dry without touching the electrode. Dip and swirl PH pen in the solution sample. Turn on PH pen. Wait for it to stabilize. Usually takes about 60 seconds for it to stabilize at a lower number. Leave PH pen in the sample solution for 20 minutes. Get new reading that is 0.2 PH higher!!!!

I tend to trust the PH reading after waiting the 20 minutes since my solution is around 67 degrees and the PH pen is calibrated with 72-73 degree calibration buffers. It is still crazy how it can differ by 0.2 when temperature does not cause that dramatic of PH swings. I just try to keep both readings within the 5.5 to 6.5 range with the 2nd reading being closest to what I actually want the PH of my solution to be.

PH pen is calibrated every other day. The calibration solutions are used 3-4 times before being replaced with fresh calibration solution. These cheap PH pens really are not cutting it anymore. Definitely investing in something better after this grow.

THCosmic · Aug 1, 2025

13th day of flowering is coming to an end. Still only the 1 plant showing pre-flower signs.

Gimme more pistils!

THCosmic · Aug 3, 2025

2 full weeks of flowering completed. Only the one plant has pistils. I decided to defoliate and prune.

Before

After

Much more breathing room underneath.

Noticed some minor signs of calcium, magnesium, phosphorous, and potassium deficiencies. This is expected as I am still transitioning my solution from veg to bloom. Added a gallon of water with increased calmag and bloom nutes.

THCosmic · Aug 3, 2025

Since I am only using 1 of my 3 tents at the moment, I decided to remove the 2 unused tents so I can convert them into curing tents. I plan to remove the last tent once this grow finishes. I will then convert the entire 5x5 closet into a grow room.

When I first built the 3 tent setup marijuana was still illegal here, so I needed tents to be able to mitigate sound, smell, and heat. Also needed to keep power usage to a minimum and on a cycle so that there are no spikes in usage. So at the time, 3 small tents made sense.

Now, marijuana is legal. You can grow 5 plants if you have a medical card, which I do. I still don't understand this 5 plant limit, such an odd number! If they made it 6, I might continue growing in a cycle with the 3 tents, 2 plants in each. But, 5 plants! So gut the closet, make 5 mobile RDWC buckets (might just do DWC using the totes I already have), hang lights from the ceiling, and grow them bigger!

Closet gutted except the tent with the current grow. I plan to remove the carpet and shelves as well. Add a 5 hooks to the ceiling for lights. I will use the 3 lights I have for the next grow and maybe purchase 2 more around flowering time. I can use the current ventilation.

New curing tent. Combined 2 tents. Inline fans at top and bottom between the 2 tents. Top blows to the right, bottom to the left, creating a nice air current. Left tent will contain a portable AC unit venting heat out the window. Need to get a 2'x4' piece of plywood for it to sit on. I think it will work out well.

THCosmic · Aug 4, 2025

16th day of flowering. The 2nd largest plant now has a single pistil showing! Still not seeing anything on the 2 smallest plants. No sign of male or female, and getting this late into flowering makes me think they will be female as well.

I will have to keep watching the pre-flowers every day keeping my eye out for hermaphrodites. Since these started as random bag seed, no point in making more random bag seed.

Pistil that blends in with the new growth behind it.

Same pistil again.

Same pistil, but viewed from opposite side.

Node above the pistil also has a pre-flower forming.

Lights are off now. When they are back on hopefully more pre-flowers appear.

THCosmic · Aug 5, 2025

17th day of flowering and the 2nd largest plant now has 4 branches showing pistils. The largest plant is filling out with pistils everywhere. The other plants are still not showing sex, but why have shot up in height.

Group

Canopy

Then lots of closeups:

MJmadscientist · Aug 5, 2025

THCosmic said:
17th day of flowering and the 2nd largest plant now has 4 branches showing pistils. The largest plant is filling out with pistils everywhere. The other plants are still not showing sex, but why have shot up in height.

View attachment 2492802
Group

View attachment 2492801
Canopy

Then lots of closeups:
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Like what you’re doing. It’s getting real cramped in that grow tent.
Good stretch going on too!

THCosmic · Aug 6, 2025

MJmadscientist said:
Like what you’re doing. It’s getting real cramped in that grow tent.
Good stretch going on too!

Thank you!

Yeah, it is definitely cramped in there. Tomorrow is my defoliation day, so there will be more room after I remove a few specific leaves. I was tempted to cut a few today, but I just did a major defoliate and pruning 3 days ago. I like to wait 4 days if any branches were pruned and 3 days if only fan leaves were removed.

I think the stretch is just about done on the large plant. The tallest branch gained maybe half an inch in the past 24 hours. I really do hope it stops, or else I will have to bend some branches to get them all a few inches lower. Last grow the plants grew up above the light and one went into my exhaust. This time I flipped them much sooner, but still might have been a bit too late. The tallest plant was 10" when flipped to flower and now it is 22".

THCosmic · Aug 7, 2025

Before defoliation.

After defoliation.

Mainly focused on removing top fan leaves that were covering other bud sites.

THCosmic · Aug 7, 2025

19th day of flowering.

The 3rd largest plant is showing pistils!!! I now have 3 females and 1 unknown. There is a very small chance the 2nd largest is a hermaphrodite. Been monitoring a pre-flower that originally looked spade-like, then turned round, then clawish, and is now opening up. There is only one node doing this and both the node above and below have twin pistils.

Pistils on the 3rd largest plant.

The possible male pre-flower on the 2nd largest plant.

Newly developed pre-flowers on the 2nd largest plant.

THCosmic · Aug 9, 2025

20th day of flowering.

Still nothing showing on the 4th plant. Used LST to rearrange some branches to even out the canopy a bit more and open up light to lower bud sites.

Group shot and canopy. I was also able to raise the light an inch or so. It definitely cannot go any higher.

My cat also loves to watch the plants with me.

Also added another LED light to help the plants busting out of the tent. I have been leaving the tent door open when the lights are on so those plants don't get the light reflected back to them. This should help them maintain their height. Will most likely have to train them to stay inside the tent though.

THCosmic · Aug 9, 2025

After adding the extra light last night, it got me thinking that I could strap another one of my lights in that tent and really max it out. Having two 140w LEDs might be overkill, but maybe one 140w and one 75w could work. The 140w has a built-in power converter, so it gets stuck in a tent, but the 75w has it separate from the light so I can put some of the heat of the light outside the tent.

I'm first going to try adding a 2nd 140w light to see if the tent's ventilation can handle the heat. If not, I will swap it out for the 75w. The 75w should barely add any additional heat.

THCosmic · Aug 9, 2025

THCosmic said:
PH meters are a pain in the ass!

Get a solution sample from my reservoir. Remove PH pen from the storage solution. Dip and swirl PH pen in fresh RO water. Remove from RO water and lightly shake out as much water as possible, then pat dry without touching the electrode. Dip and swirl PH pen in the solution sample. Turn on PH pen. Wait for it to stabilize. Usually takes about 60 seconds for it to stabilize at a lower number. Leave PH pen in the sample solution for 20 minutes. Get new reading that is 0.2 PH higher!!!!

I tend to trust the PH reading after waiting the 20 minutes since my solution is around 67 degrees and the PH pen is calibrated with 72-73 degree calibration buffers. It is still crazy how it can differ by 0.2 when temperature does not cause that dramatic of PH swings. I just try to keep both readings within the 5.5 to 6.5 range with the 2nd reading being closest to what I actually want the PH of my solution to be.

PH pen is calibrated every other day. The calibration solutions are used 3-4 times before being replaced with fresh calibration solution. These cheap PH pens really are not cutting it anymore. Definitely investing in something better after this grow.

I caved and bought an $80 Apera Instruments AI311. I was going to get the Bluelab, but I didn't like the idea of paying an extra $20 and not having 0.01 accuracy. It would cost $250 to get 0.01 accuracy with the Bluelab OnePen. It does include EC and app tracking, but those are really unnecessary. I never have a problem with EC meters, even the cheap $10 ones work fine. It is always the PH pens that fail and PH is more important than accurate EC. For EC, I only care if it goes up or down over time, not the exact number.

Another major factor is the cost of the replacement probe. Apera is only $26 while the Bluelab OnePen is $99 for its replacement probe. I can replace the Apera probe 6 times and still be under the cost of initially buying the Bluelab OnePen. The OnePen also has 20% of its reviews as 1 star, so something is up with that specific product.

THCosmic · Aug 9, 2025

THCosmic said:
After adding the extra light last night, it got me thinking that I could strap another one of my lights in that tent and really max it out. Having two 140w LEDs might be overkill, but maybe one 140w and one 75w could work. The 140w has a built-in power converter, so it gets stuck in a tent, but the 75w has it separate from the light so I can put some of the heat of the light outside the tent.

I'm first going to try adding a 2nd 140w light to see if the tent's ventilation can handle the heat. If not, I will swap it out for the 75w. The 75w should barely add any additional heat.

Added both the 140w and the 75w. Now there are two 140w lights above canopy and the 75w light under canopy.

Canopy temp went up about 5f on average. Sits just under 83f. I want to get it under 80f. If I can do that I will keep all the lights in there. Though the 75w light is just sitting there and may be removed completely.

2x2 RDWC #4: Test with Bag Seed

2x2 RDWC #4: Test with Bag Seed

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