The myth, of the high P myth?

[spurr]

I am trying to find a KISS method of hit some nice ratios. I am currently using spurs 5/5/5/5 with Roots excel and GO Bioroots in Veg. DTW coco/perlite and loving it. Just tired of having so many nute bottles.

CNS-17 flower @20ml gallon
121N 53P 252K 121Ca 30Mg 69S

adding 5ml gallon sweet bumps the MG to 53Mg and 99S

any thoughts?


my flora stuff is running out so try and to get flower nutes here in a week

20 ml/gal CNS-17 and 5 ml/gal Sweet:

NO3:S = ? (what is the NO3 ppm?)
P:S = 0.54
K:Ca = 2.08
K:Mg = 4.75
Ca:Mg = 2.28
K|Ca|Mg = 4.6|2.3|1

 

[spurr]

edit...and for the record Spurr nailed it. Those trichs are off a freak f2 Deep Chunk x Haze by Tom Hill. My guess is the entire plant may yield 1/4 ounce...but it is a mind blowing 1/4.

I will be PMing you may safe address for cuts soon ! (kidding )

 

[spurr]

Spurr do you run your recipe throughout bloom or do you ever spike Your K levels up?

Yes, same mix from veg to harvest, no spiking of anything; I normally I do not 'flush' either. One of my biggest yields (in terms of gpw) with 5 ml/5 ml/5 ml/5 ml/2.5 ml/0.5 gram was ~1.75-2 lbs from 600 watt Hortilux SuperHPS and NextGen ballast (no Co2); growing LUI.

The pH/Lucas mix is meant to be used in the same manner, IIRC, no spiking just the same mix from veg to harvest.

I do tend to water with organic amendments (cool processed kelp extract, fulvic acid, humic acid, vermicompost/vermicast extract and sometimes fish hydrolysate) in between fertigations, though. That helps keep the elements in soilless solution closer to what I want ...

I know how you don't like pure flowers but......if trying to raise K lvls and keep P low.....since it takes like a year for the P to to be available it sounds like a great way to raise just K.

It's not that I dislike phosphites ("Phi", e.g., Pure Flowers), it's a fine product but it's a terrible source of P for the plant. What bother me is it's marketed as a P and K booster ... lies, it's not a P booster for the plant. That said, yes, Pure Flowers could be a good source for K, as well as other benefits from phosphites such as being a fungistat and inducing SAR like response. The problem with Phi is it can hinder plant uptake and usage of Pi (phosphates, i.e., P for the plant) and phosphites are not the healthiest things to consume (they are systemic in plants and last a long time, up to and more than a year).

If you want to boost K with an off the shelf product, why not use something akin to ProTeKt (i.e., potassium silicate)? (FYI, plants use Si in the from of "silicic acid")

 

[spurr]

@ all,

Here are some pics, plants are on day 12 of flowering now ... sorry pics are crappy, they are from my cell phone.


Week 4 to 5 of veg from seed; P was ~39 ppm

F4 GrapeGod (GodBud x Grapefruit) from NextGeneation Seeds (feminized). I had a heat issue that affected the plants a little at that point, heat issue now fixed via IceBox and 1 HP water chiller.​

Day 12 of flowering; P is ~53 ppm:

Some plants are out of picture frame and pics where taken under 1,000 watt MH, so the leaf color is not 100% accurate, e.x., the center of canopy looks yellowish, but it's not.​

 

[spurr]

Guard dogs ... GRRR!!!

Both are rescues, I foster for a no-kill adoption group.

(pit/boxer mix)

(pit)

 

[YosemiteSam]

You definitely have the canopy full. Nice color, no burnt tips and all of the leaves seem to be flat to the light..all systems go it looks like to me.

Mind if I ask about humidity/temp? Are you using VPD? What I find is that at least through stretch that is the way to go and makes for explosive growth. But if I stick with it through the rest of the grow mold always becomes a possibility. I tend to back the humidity down after stretch.

Anyways..hope airflow is excellent in there. It is going to get some crowded. And good on ya for the dogs.

 

[spurr]

You definitely have the canopy full. Nice color, no burnt tips and all of the leaves seem to be flat to the light..all systems go it looks like to me.

Lets hope so!

Mind if I ask about humidity/temp? Are you using VPD?

Yes, I use VPD to quantify RH/temp affects on plant (re rate of transpiration, stomatal conductance, water use efficiency, etc.). I use VPD of ~1.0 to 1.3 kPa, I try to keep it below 1.20 kPa. The range is due to leaf temp differences throughout the whole canopy. Some leafs are a few degrees cooler than others, which strongly affects VPD.

Because I use carbon filter for smell, I don't let my RH get above 55% (max 60%). This is because carbon filter won't work once RH exceeds ~65% RH. Thus, to keep VPD in ideal range (0.8-1 kPa, up to 1.25 kPa) I need to keep canopy temps at 75-78'F, which means leafs temp is ~72-76'F. I use Co2 at an ideal rate of ~700-800 ppm (I use a "dif" of 50 ppm via "fuzzy logic" Co2 controller). Because I use Co2 I would prefer to let my canopy temp reach 80-84'F, but that isn't possible whilst also keeping RH < 60% and VPD < 1.3 kPa.

I use a high quality IR gun to test leafs temp and canopy temp (via white piece of paper not in direct light) and a very high quality (NIST certified) analog hygrometer using synthetic hair to test RH. I calibrate the hygrometer weekly.

What I find is that at least through stretch that is the way to go and makes for explosive growth. But if I stick with it through the rest of the grow mold always becomes a possibility. I tend to back the humidity down after stretch.

In my experience, mold issues relative to VPD are not a problem if VPD is > ~0.4-0.6 kPa and canopy/leafs temp is not so high it would make RH be > ~65-70% for VPD of ~1.0 to 1.3 kPa. Once VPD is about and less than 0.2 kPa and/or RH is about and greater than 70%, mold issues and other fungi can become a problem. That said, for very dense buds with little air flow through the canopy mold issues are more of a concern ...

I keep VPD at 1.0-1.3 kPa from veg to harvest, as long as I keep RH < ~60% due to carbon filter issues and mold/fungi issues. However, I also have LOTS of air movement through canopy.

IMO it's very important to keep VPD in, or close to, ideal range (i.e., <1.3 kPa) during bud-set and bud-formation for various reasons outside the scope of this thread (re yield, Co2 fixation, radiation use efficiency, rate of photosynthesis, Ca and B uptake and translocation, etc.)

Anyways..hope airflow is excellent in there. It is going to get some crowded. And good on ya for the dogs.

Yup, air flow is better than in most other peoples gardens even outside a tent, guaranteed. I do not close that tent 'door', it stays open 24/7 and I have a 4" outlet fan at the top of the tent with a 4" inlet fan at the bottom of the tent; as well as osculating fans inside the tent hanging from walls and the air flow from the IceBox from the 8" vortex fan attached to the hood. Air temp coming from the IceBox, not vented from the tent, is ~ 68-70'F. I keep my rez for the IceBox at 61-63'F, just high enough to prevent condensation (re Dew Point), but low enough to cool the room so I don't need A/C.

I used a tent this time, normally I do not use a tent (that tent is a 5'x5'). I used the tent for the following reasons:

• increase red:far-red ratio (to reduce stretch/internode elongation)
• increase irradiance from reflection (I try to provide greater than (at least) 800 umol/area/second, > 1,000 umol/area/second is my 'ideal', for all plants but that's not possible without a light mover)
• reduce IR 'footprint' that LEO could 'see' with something like FLIR

FWIW, I also use a zero to -5 DIF during pre-flowering by heating during nightlength. I heat during the night equal to, and just above, temp during daylength. I.e,. night temp is ~75-83'F and day temp is ~75-78'F. This grow I kinda messed up and placed the heater way too close to the plants, so some of them had slight leaf chlorosis and lost some leaf pigmentation (Chl A and B). Once I moved the heater back and changed to a zero to +5 DIF the plants were much happier. Once the stretch period of pre-flowering is over I change to a +5 to +10 DIF and then late in flowering I change to a +10 to +15 DIF to increase leaf/bud color via affecting (increasing) anthocyanin (a type of flavonoid).

 

[spurr]

@ YS,

The way I grow in terms of environment (re VPD, DIF, Co2, irradiance, etc., etc.) means most people would be unable or unwilling to emulate me because it costs a pretty penny and takes a good amount of setup and tweaking time to get 'just right'. I spent about $6,500 on the setup in the pics above; and I got a discount of about $1,000. So for someone else to buy my setup would cost $7,500. Granted the most expensive equipment, ex., Co2/environment controller, uber-customizable multi-equipment timer (20 amp), quantum sensor and data logger, 1 HP water chiller, Galaxy select-a-watt, 8" BlockBuster, etc., are out of the picture frames.

I didn't mind spending that much for only a 1 kw grow because on my next grows I can simply add more lights (not using the tent) without spending more on high tech and high end equipment (besides a few more LightRail 3.5 movers). Basically, what I bought is scalable, I can use it for a single 1 kw grow or a multi-kw grow well into 8-10 kw.

I did buy some things I do not need, though, but we live and learn I guess. I kind of 'went nuts' on my shopping spree.

I believe I will pull > 2.5-3 lbs from this grow, if the GrapeGod are as heavy as they are claimed to be. If that is the case I consider the money well spent because around here a pound of dank goes for ~$5,600-6,000 wholesale. Even if I only pull 2 lbs I would be happy in terms of return on investment ...

 

[YosemiteSam]

Grapefruit is a really big yielder. I have seen it grown. God bud is also suppose to be a big yielder. So you got the potential.

Good luck on the grow.

You want expensive. 3K for a dehuey here and I really should add a little more. But like you imply...there ain't that many businesses that can return your capital in 3 months.

Deep down 3 lbs per light is my goal also.

 

[spurr]

3k on a dehuey, damn, that's pricey, must be a Cadillac and huge to boot!

To grow the best we gotta be willing to kick down some cash I guess. I would rather spend a few thousand on increasing my grows profitability than simply putting the money under my mattress.

 

[DonkDBZ]

P.S. I know you're trying to go KISS, but if you have an itching to try something may I suggest giving my current test mix a try?

• 5 ml GH Micro
• 5 ml GH Grow
• 7 ml GH Bloom
• 5 ml CalMag+
• 2.5 ml ProTeKt
• 0.5 gram Epsom salt

my 2 cents ...

So thats I am currently running your 5/5/5/5 with 5 ml silica blast, 3ml sweet, 2-3ml bioweed, 5ml bioag fulpower and 1 ml roots excel. prefectly green stems, super healthy. added some bioroots @ 10ml for shits and grins but it messed up the ratios and stems started to purple so I took it out.

If your mix can yield that well. I will just run it all the way through. Guess I need to get out of the habit of wanting to blast my K real high. Looking back at my own records one of my best runs was like 100N 60P 190K with tap water. 1lb 4oz off vert 600

 

[spurr]

@ Avenger:

Good point re humidistat vs hygrometer. I meant to write hygrometer but I was thinking humidistat, which is what controls a humidifier or dehumidifier, e.x., for automation. A humidistat has a hydrometer included, that is how I automate RH control, but I use my high quality (NIST certified) hygrometer to make sure the RH is correct. Ex., the Sentinel CHHC-4 I use is way off in terms of RH from its hygrometer; it's about 10 point too high, the same goes for the Titian humidistat I use. So I must set both of them 10 points higher than I want because they are SO very inaccurate ...

Thanks for pointing that out to me, I am going to fix that typo now

 

[poipu79]

So how does one figure out if which the .5% G.A. of Mg provides, 5ppm of 13ppm of mag?
and how much S?

Thanks, O

hey O...the %on the label is the same as the result of a 1g to 1L of water or g/L formula
my package of magnesium sulfate is labeled 9.8% Mg 12.9% S

all I see when I look at the label is 98ppm Mg and 129ppm S when added at 1 gram per litre of water
I look at all fert labels that way grams per litre or mls per litre
of coures P and K get hit with .44 and .83 but you prolly know that

poipu

 

[Avenger]

Spurr,

Have you been playing with the licor quantum meter much?

 

[spurr]

yup.

 

[Overthinker]

hey O...the %on the label is the same as the result of a 1g to 1L of water or g/L formula
my package of magnesium sulfate is labeled 9.8% Mg 12.9% S

all I see when I look at the label is 98ppm Mg and 129ppm S when added at 1 gram per litre of water
I look at all fert labels that way grams per litre or mls per litre
of coures P and K get hit with .44 and .83 but you prolly know that

poipu

poipu,

Thanks for the input. With most things you can assume I probably don't already know. lol
I am still very much in the learning phase with really understanding the chemistry behind all this stuff. Anyways, I vote you do more participating in the discussion and less lurking. You seem to be in the "more knowledgeable" class of folks around here. The more brains the better imo.
I am truly appreciative of folks around here being so willing to share their knowledge with others. It really helps those trying to understand the finer details of things.
O

 

[YosemiteSam]

Spurr...you stated ideal CO2 ranges are 7-800 ppm.

Do you have a citation for that? I have been running at 1500.

 

[spurr]

YS,

Yes I do, I wrote posts in another thread on this issue within the science sub-forum. Co2 saturation point for most higher C3 plants is ~1,000 ppm; thus for that fact alone 1,500 ppm is far too high. There is no scientific evidence (I or others have been able to find) backing up the claim of 1,500 ppm Co2; it's just something Mel Frank, et al., wrote and no one ever bothered to question.

Shortly for now, high Co2 above ~1,200 ppm can/does hinder (reduces) "Rubisco activase", which in turn hinders (slows/reduces) conversion of "inactive Rubisco" into "active Rubisco"; and that in turn reduces Pn (rate of photosynthesis) because Pn depends upon active Rubisco. Not only that, but higher Co2 also reduces stomatal conductance (openness of stomata), which in turn hinders other things like Ca and B uptake, water use efficiency, Co2 uptake and carbon fixation, etc.

I and others have tested ~1,000 ppm (and lower) vs 1,500 ppm and there was no yield/growth increase at 1,500 ppm vs < ~1,000 ppm. Granted, the testing methodology was rather poor ...

Just like in fertilizers, it's best to offer sufficient level of Co2, not over apply, and 1,500 ppm is way over applying Co2.

 

[spurr]

Oh yea,

In terms of studies on cannabis and Co2 relative to Pn, 750 ppm was found to be better than less than 750 ppm; but higher than 750 ppm was not studied. In the (near) future I plan on studying this issue with high tech analytical tools to gather solid data on Co2 at 700 ppm vs 1,000 ppm vs 1,500 ppm in terms of Pn, Rubisco, Rubisco activase, Gs (stomatal conductance), Co2 saturation point, etc.

 

[spurr]

I use 700-800 ppm Co2 for a couple of reasons:

1. those I wrote about above

2. so a 20 lb tank of Co2 lasts long so my neighbors don't see me bringing said tanks into my house (as often)

3. so I don't have to vent the room at night to drop Co2 ppm in terms of Co2 at night, which will reduce plant dark-respiration (a good thing to reduce stretch). I try to keep Co2 < 800 ppm at night (ideally < 600 ppm) because too much Co2 at night is not good and can make plants become yellow and slow growth ...​

Okay, I'm off my Co2 soap box