Delps 8 Hydro RDWC Gelato Autoflower 2021

[Delps8]

HERE’s something

Excellent! I've seen the first graphic but not the article. That was the key part.

The light curve in this article is essentially the same one that's on the photone site. Why the huge drop off in DLI from veg to flower?

The message I remember from Bugbee is "Pour it on, baby!" Granted, he's selling light meters but he does have significant credibility and other researchers have found similar results. When I looked at the Chandra paper, the target environment that I formulated was 85° and a DLI of 45'ish. That's a PPFD of 700 on 18/6. I remember what the light cycle was but, if that's 12/12, that sets the floor at a DLI of 30 at 400 PPM.

The second graphic is really helpful. At 400 PP of CO2, once you get to a PPFD of 600, the law of diminishing returns is quite significant. That PPFD for 18 hours is only 38.88 so there's not much benefit of my to going to 40-whatever but the plant, generally speaking, will continue to flourish.

Great to know - thanks for the link.

 

[Delps8]

Day 50.

Plants are looking good - short and squat, except for that tall fella, but good.

pH drops over night, faster with the new res than with the previous res. It’s 6.0 at 2300 and 5.4 by 0800. When I win the award for “Weirdest Canopy”, I’m going to spend part of my winnings on a pH doser.

Per above, canopy is now categorized as “weird”. I mean really…anyone can grow a perfectly flat canopy, right? It takes real skilzl to come up with a canopy shaped like a fainting couch!

Two pictures - before and after super cropping two of Jeff’s stems. I’ve attached the PPFD distribution with and without Jeff, as well. With just Winnie and Mary, the canopy is, arguably, perfectly flat if you take into account that the Apogee is has a tolerance of 5%±. That's probably a CYA thing but, regardless, the canted light is doing the trick. Fortunately, these plants are all the same strain or else some would be taller than the others!

My last grow had a big variance in height, as well. 1 at 24”, 1 at 30”, and two at 40”. One way to solve that issue — grow one plant. Mary is taking up the entire left side of the res. My thinking is that I might have been able to get her to cover a lot more of that tent if I’d just plopped her in the center net pot and LST’d like fury. A photo could fill the tent much more easily than an auto and I just happen to have some ChemDawg, GG, and one other set of seeds that are photos. Might be interesting to try that after this grow.

The plants are starting to go vertical as we move into week 8.

No trouble keeping the tent temp in the 80’s as today’s high was 96°, heat courtesy of the second day of Santa Ana winds. It’ll be in the high 80’s for a couple of days and then back to the 60’s. Dry as a bone out there, too. Current RH is 18%, maxing out at 24% at 0400 tomorrow.

 

[Delps8]

OK, the weekend has arrived.

"What's a week end?" [Downton Abbey reference].

Lots of heat outside today with shade temps over 90°F. So, "Waxing up the sled for Thanksgiving?" is not a remark made in millennia here in SoCal.

Then the roommate drives her car into the garage. Temp rose from 82° to 89° degrees in three hours. Nice smoooooth way to end the week, eh?

All I could do was let Wetbird (the Inkbird RH controller) do its thing. All I had to do was open the tent doors for a bit.

This looks like one of many "good to watch" videos but what struck me was the body language of the interviewees at the 4:48 minute mark. Very good info there - back to watching it.

 

[Delps8]

pH fell again over night. I'm getting used to the drill now. Add some Up early AM and they a couple more shots during the day. I'm not seeing any kinds of issues with the plants.

I did have concerns about using a dose. pH dropping is a message so why mask what the plant is telling me? Because I have to add Up three times a day, that's why. Also, from a market perspective, if using a doser was not considered a valid approach to horticulture, the market would indicate that, meaning that we wouldn't have multiple companies manufacturing and selling them.

Given my lack of desire to manually add Up every N hours, I checked out the Bluelab doser at Amazon the other day and was surprised that it was just a bit over $300. I should have bought the damned thing because, when I checked it out last night, the price was $441. I must have been mistaken about the $300 price - I can't imagine that big a price chance but I sure would have liked to have been able to get one at that price. I've added the doser to my account on camelcamelcamel - maybe there will be a Black Friday surprise.

 

[Delps8]

Day 51.

Spent some time in the tent. About 2 gallons of water, a factor being the heat in the tent yesterday. Added 2 RO.
Attachment shows the leaves from the undergrowth.

 

[FelipeBlu]

Heat is hard to keep up with!

Those leaves show indications of Mg, N and K def. Pretty old leaves - so those days are behind us, right?

 

[Delps8]

Heat is hard to keep up with!

Those leaves show indications of Mg, N and K def. Pretty old leaves - so those days are behind us, right?

Yes.

The nutrient issue has been resolved, thanks to you.

The pH dropping thing? I'n not seeing any issues with the plants.

Turns out the heat today was a non issue but that's how Santa Ana's are - sometimes it's just one day, sometime's it's a week. I lucked out this time.

When I checked the tent, some of the Mary's leaves under the center light bar appeared to have the inverse of inter veinal chlorosis - it was…"inter veinal darkening"?

I'll check that when I "walk my rounds" later tonight.

 

[Delps8]

Day 53.

pH has been stable at 5.9 since this time last night. Very happy to see that but noticed that some of the leaves are dark green and are getting chlorosis.

The res is 5 days old. It seems that the pH drops diminish as the res gets older. Just an impression - haven't looked at the numbers.

Anyway, something's going on with May, the largest plant. Winnie and Jeff are doing fine. Is this another Ca MG issue?

 

[FelipeBlu]

I’m not seeing anything alarming. Are you talking about the newest yellow-green growth?

 

[Delps8]

I’m not seeing anything alarming. Are you talking about the newest yellow-green growth?

Day 54.

Yes.

Before I jump into that - big water overnight. Water level dropped 23 mm which is ≈ 2.6 gallons. More good news - TDS dropped. It was ranging 410-430 but the range has dropped over the past two days and it’s firmly sitting at 390.

Wait! There’s more! pH was at 5.9 as of yesterday AM, it touched 5.8 for < 1 hour, went back to 5.9, hit 6.0 by 2300 yesterday, and has remained at 6.0.

I need to add water. If I add all RO, TDS will drop to 355. Given that the plants are reacting “normally” (they’re drinking and eating) I’m leaning more toward leaving the TDS at its current level. Does that sound right?

DLI is hard to state because of the uneven canopy. Overall, the DLI is about 49 but the center of the tent is (was) at a PPFD of 886 and the lights ran 19/5 yesterday so that’s a lot of light. Based on what I’ve seen over the past week or so, without CO2, cannabis cannot photosynthesize > 900 µmoles. Unfortunately, those very sage sources convert that to DLI for photos which is where we get the unusually shaped graph that shows DLI dropping in flower and then rising but, for autos, lacking a need to switch to 12/12 for flowering, I’m moving to the conclusion that it’s one of those “how fast do you want to spend” issues. The X3 is cheap to run - the difference between 200 watts and 350 watts is just under $20 per month even with the pricey electricity in SoCal so I’m going up the wattage and see what shakes out.

New pix attached. Under natural light, the leaves appear healthy but they are quite dark.

The third image is a followup of a picture from Mary the other day.

The circle in the last picture shows the area that Winnie occupies. I’m concerned about the impact of having that much foliage in the tent. I’ve got fans blowing along the res top and there are no sign of mold but there’s something about having a very small plant with very dense growth that concerns me. In the movie “Amadeus”, one of Mozart’s benefactors remarked about the symphony having “simply too many notes”

 

[FelipeBlu]

Given that the plants are reacting “normally” (they’re drinking and eating) I’m leaning more toward leaving the TDS at its current level. Does that sound right?

If you believe that 355 ppm is too low, then I guess you could call 390 the lower limit and time to change the reservoir. If you’re asking if it’s a good idea to just add water and fertilizer to the existing reservoir to hit some TDS target - remember, there are plant exudates in there, and no way to know what exactly the plants have already consumed.

This yellow-green new growth is typical in a fast-growing plant. It isn’t usually an indication of deficiency, and those leaves should green up as they get a little older.

 

[Delps8]

If you believe that 355 ppm is too low, then I guess you could call 390 the lower limit and time to change the reservoir. If you’re asking if it’s a good idea to just add water and fertilizer to the existing reservoir to hit some TDS target - remember, there are plant exudates in there, and no way to know what exactly the plants have already consumed.

Understood.

If I add only RO, the concentration of all nutes will drop and the nutrients that were consumer will not have been replenished.

If I add fresh nutes, that increase the concentration of the solution and will restore some of the nutrients that were consumed.

I would think that I want to restore the nutrients that the plant consumed, right?

This yellow-green new growth is typical in a fast-growing plant. It isn’t usually an indication of deficiency, and those leaves should green up as they get a little older.

Great! I don’t want to go through that deficiency issue again. Once was more than enough.

 

[FelipeBlu]

If I add only RO, the concentration of all nutes will drop and the nutrients that were consumer will not have been replenished.

If I add fresh nutes, that increase the concentration of the solution and will restore some of the nutrients that were consumed.

I would think that I want to restore the nutrients that the plant consumed, right?

I would agree. The question is whether you change out the reservoir - and know that everything in the TDS is going towards plant nutrition - or add nutrients to the reservoir and possibly increase the TDS (existing TDS plus whatever you think the plants need).

 

[FelipeBlu]

Here’s one way to look at it..

If you would want a fresh reservoir to start at 700 ppm, then the best you can do with the current reservoir is to add 310 ppm of new nutrients (700- current TDS of 390 ppm) - and you really have no idea how much of the current TDS is useful to the plant.

 

[Delps8]

Here’s one way to look at it..

If you would want a fresh reservoir to start at 700 ppm, then the best you can do with the current reservoir is to add 310 ppm of new nutrients (700- current TDS of 390 ppm) - and you really have no idea how much of the current TDS is useful to the plant.

However, we can infer was was consumed because “some people” know that cations were being munched.
OTOH, though theTDS drop was minimal, it coincided with rising pH. I’ve got to believe that was cause and effect.

Perhaps the reason for the drop being so small is that I’ve got 28 gallons of nutes and three relatively small plants ≈ 9 gallons per plant. That’s a lotta watta.

I’m planning a res swap tomorrow, BTW.

 

[Delps8]

TDS is now 370-380 (vs 390-410) and pH rose to 6.1.

 

[Delps8]

The absurdity continues. Flowering continues apace and the canopy continues to become more lopsided. The light is canted at a crazy angle but it's serving its purpose - all areas of the canopy have a PPDF of > 500 µmoles.

Mary's canopy is 12" to 15" tall. She had a lot of LST and you can see where the branches are by following the lines of buds that radiate to her left.

Winnie is "stuck in the middle". She's got a huge amount of foliage and not many bud sites though the few that are on the plant look monstrous compare the Mary. She's being enveloped by Jeff's growth.

Jeff continues to dominate. Branches everywhere, covered in bud sites. I'm continuing to super crop some of the growth.

Res swap went well. The res ended up at 390 which was exactly the TDS I wanted. 28 gallons in the barrel ==> 28 gallons in the res. Good stuff. TDS dropped steadily hitting 350 today. Dropped in 2 gallons of the 4 gallon 100% strength batch of nutes that I create before I do the big batch. That raised the res to EC 0.8 so we'll see if we get nute burn or maybe the plants will do better with it since they're older.


Water consumption has been significant even thought RH is in the 60's and 70's. The reason for the RH being that high is that I'm keeping the temps in the high 70's and low 80's and I need the elevated RH to keep VPD at 1.0.

Question -
Now that the plants are well into flower (vs pre-flower), is it better to keep temps high (which requires higher RH) in hopes of increasing yield or is it better to drop the temps into the 70's so as to allow RH to fall into the traditionally recommended range for flower?

My inclination is the latter but I'd appreciate input on that.

 

[FelipeBlu]

My inclination is the latter

Mine is too - I think it’s good practice to keep RH lower during flowering - for a variety of reasons - including mold paranoia.

 

[Delps8]

For the most part, plants are doing well. Per the “Res Closeup”, Jeff continues to dominate the skyline, Winnie is crouched down on the center right (I’ve drawn a circle around her), and Mary is sprawled over the left half of the res. Mary is, roughly, 12” tall; Jeff is, for the most part, 36” tall. Nice even canopy, eh?

Thinking of which - I’ve had the X3 running at 300 watts for a few days. Per the light distribution attachment, quite a bit of the canopy is getting > 900 µmols, which seems to be the level above which cannabis cannot absorb light barring CO2 enrichment. That’s fine by me - even at the award winning prices for electricity in South PRC, the additional cost is, at most, a few dollars a month. My main concern is ensuring that the grow is getting enough light without any damage to the plants and I think I’m hitting that mark.

pH continues to drop. I’m adding Up three times a day. AM reading has been 5.5 to 5.7, varying with when I take a reading, so I Up it to 6.0 which drops to 5.7± by mid-afternoon which gets another 3 ml Up which drops to 5.7± by 2300 which I up to 6.0±. Lather, rinse, repeat. I’m still on the fence about the doser. If anyone’s interested (hah, hah), the Bluelab doser with the Connect ability is currently cheaper ($421) than the doser without the ability to use the connect dongle ($441). Supply and demand - quite something, eh?

Per attachments, some of the leaf tips on Mary are damaged. It looks like nute burn but the EC has been between 0.74 and 0.8 - that’s a reading from the Bluelab monitor which is reading 40 PPM high compared to the pen so the really EC is down around 0.66. Wow.

Time for a res change and, since the plants are well into flowering, I’m wondering if the NPK values need to be adjusted. Perhaps @FelipeBlu could weigh in on that?

I’m sorta getting used to my new growing style - I call it “HOG” for “hill of green”. Seriously, it totally sucks. I’d much rather have a couple of LST’s plants with colas coming up from a 12” tall plant that 24” wide than a gangly, 3’ tall plant that has stems reaching every everywhere. Strangely enough, Jeff has been topped, LST’d, and super cropped yet the plant is still 3 times the size of the other two.

The “Tent Frontal” shot - just added that because it’s nice to have the tent open. The dehumidifier keeps the RH at 40± and the garage is still pretty warm so it’s easy to have maintain a VPD of 1.3 to 1.4. The Pulse is reporting 78.6°F and 64% RH.

 

[FelipeBlu]

Per attachments, some of the leaf tips on Mary are damaged. It looks like nute burn but the EC has been between 0.74 and 0.8 - that’s a reading from the Bluelab monitor which is reading 40 PPM high compared to the pen so the really EC is down around 0.66. Wow.

Time for a res change and, since the plants are well into flowering, I’m wondering if the NPK values need to be adjusted. Perhaps @FelipeBlu could weigh in on that?

Frankly, the leaves in the photo below hardly look like excessive nutrients. To me, it looks like the early stages of K def. I would bump the dose.