420 Magazine's Official Girl Scout Cookies Comparative Grow By Brett Blaze

Elevated Lighting Company

Well-Known Member
It is neat to see the variance in the leaves. The ladies are stacking nicely.

I have personally grown a few different variations to GSC. Interested to see the final bud.


Plant of the Month: Sept 2021

Brett Blaze

Well-Known Member
@Brettblaze have you considered lowering your starting nutrient mix ppm?
Thank you for the input.

I reduced the total starting solution ppm over a week ago when the yellow "streaks" showed up. I went from 1685 ppm to 1285 ppm by removing Terpinator and Cal-Mag. In the latest batch of solution I added the minimum Cal-Mal raising it to 1385 ppm.

I'm looking to reduce the output ppm difference from the input ppm. Output ppm minus input ppm needs to be 200 or less. So if I went down to 1200 ppm to start and my output was over 1600 ppm (400 ppm difference) there is still too high ppm in the runoff since it's still over 400 ppm difference. My output was at 2000 ppm last night even after lowering the input to 1285 ppm as a starting ppm and watering 4 times a day with plenty of runoff for over a week.

Current Solution:
Base tap water 165 ppm
@Prescription Blend Nutrient Solution 1120 ppm
Cal-Mag 100 ppm (3 ml per gallon)
Total Solution - 1385 ppm

I think the flush may help since the runoff number difference was cut in half after the flush and this morning it was at 200 ppm difference or less. Both plants looked fine this morning after 12 hours of light.


Brett Blaze

Well-Known Member
Two leaves show different phenotypes as well.
Both leaning towards Sativa but #1 more so. Could be a reason for the color. Even the purple stem could be genetic and not an issue. Both produced multiple 13 finger leaves and remember #2 has twin buds on a few branches and some areas what looks like a triple bud. No twins on #1.

Brett Blaze

Well-Known Member
Daily Update -

Stage - Flower Day 29 - 80 days above ground
#1 Bloom Day 12
#2 Bloom Day 17

Fertigation has been pretty good and I finally have the output of each fairly equal. I have a new timer coming today with the ability to set seconds. Now that the output is fairly equal I can fine tune with the new timer. Total output was a little high so reducing the time by just a few seconds should get me close to my objective of 10% to 20% runoff.

Output ppm for last night and this morning continue to look good but near the limit to where need to still watch closely.

Last Night's readings: Input 1385 ppm.

Output #1 1550 ppm (165 over) #2 1625 ppm (240 over). a little high.

This Morning's readings: Input 1450 ppm. Not sure why the ppm increased overnight. I measured several times.

Output #1 1640 ppm (190 over) #2 1640 ppm (190 over). Both had the same output ppm.

Both ladies are the same height as the last few days so stretching may be over. #1 sits at 23.5" and #2 at 26.5". #1 stacking is starting lower as well.

I removed three front branches from #1 this morning that were m not going to stack.

Today's Photos:

:peace: :passitleft:

Elevated Lighting Company

Well-Known Member

Brett Blaze

Well-Known Member


420 Staff
You should enter that last photo in one of the contests. It really is glorious.
These amazing photos, extensive commentary and attention to detail are why I recruited Brett for staff. Hoping he mentors more to follow suit, as we need to expand our team. Looking forward to your reviews coming soon brother, it's almost time :high-five:

Brett Blaze

Well-Known Member
Daily Update -

Stage - Flower Day 30 - 81 days above ground
#1 Bloom Day 13
#2 Bloom Day 18

With the new timer giving me seconds adjustments vs minutes I can dial in the amount of input better. Last nights auto fertigation went ok with #1 outputting twice as #2 at 2 minutes. I made a slight tweek this morning and reduced the time to 1:45 and so far it looks pretty good. The cup in the photo is 16 oz. (475 ml). The goal would be 1/4 to half full. It's still dripping slowly when I took the pic. Lights are now out but I can still see the liquid level in the cup from the Tent Cam. Crossing my fingers this time.

I am currently fertigating 3 times a day. I believe this currently works best right now and may go to 4 later in flower. These occur a few minutes after lights are on 9:00 PM, 6 hours after lights are on at 3:00 AM and right before lights go out at 9:00 AM. The 9:00 PM and 9:00 AM for the most part are hand watered and I only use the timer for the 3:00 AM fertigation. Some of the 9:00 AM and 9:00 PM fertigations have used the timer to adjust flow.

Last Night's readings: Input 1430 ppm.

Output #1 1700 ppm (270 over) #2 1640 ppm (210 over). Both up since the last measurement yesterday..

This Morning's readings from 3:00 Fertigation: Input 1430 ppm.

Output #1 1730 ppm (300 over) #2 1760 ppm (330 over). Output numbers are rising again.

This Morning's readings 9:00 AM: TBD Output quantity so far looks good.

Today's Photos:

Tent Cam of #2 output. Still dripping but appears to be between 25% and 50% when finished.

:peace: :passitleft:

Brett Blaze

Well-Known Member
Daily Update -

Stage - Flower Day 31 - 82 days above ground
#1 Bloom Day 14
#2 Bloom Day 19

I am a little over the halfway mark in flower and predict about 4 more weeks until harvest. I made a new batch of solution last night with some minor adjustments. I added some Hydroguard to reduce anaerobic bacteria that develops particularly in reservoirs. I used this with my DWC systems and I should have introduced this into my reservoir a few weeks ago. Anaerobic bacteria can dominate the system, locking out available nutrients and creating root rot.

I also added some raw yucca to the solution which acts as a wetting agent to reduce the surface tension of the water. I found this remedy searching online and haven't tried it before. This should help the drip ring dispense the water more evenly and keep them from getting clogged. It also helps the lateral movement of the water in the media.

Another adjustment, per the @Prescription Blend program, was to reduce the Big Data component back to 5 ml per gallon from the 6 ml per gallon for flower weeks 3 and 4. Big Data is the phosphorus and potassium containing supplement for the program. Both are essential during the flowering stage.

This Morning's readings from 3:00 Fertigation: Input 1465 ppm.

Output #1 1820 ppm (355 over) #2 1740 ppm (275 over).

This Morning's readings 9:00 AM: Input 1465 ppm.

Output #1 1830 ppm (365 over) #2 1875 ppm (410 over).

Because I am seeing output ppm rising up to the 400 above input level I am going to do a partial flush this evening. I will reduce the input solution by 50% and add some Flora Kleen to the flush solution. Flora Kleen will help break up the salts allowing me to flush with less solution.

The DEMON LED light from @Elevated Lighting Company (formally know as Budget LED) is turned up to 100% at 18" above the top of #2. It's putting out 955 PPFD at 56K Lux. The tent temperatures are staying below 84° F even during the peak hours of the 12 hr. lights on period. This is with nighttime outside temps near 100° F at midnight. Average tent temps are 82°F during lights on.

Humidity is now getting to be an issue. I have been averaging 57% with up to 67% during the lights off period. With RH only about 20% and sometimes down to 5% outside I would have expected lower RH indoors. The tent room is t 50% with the door open. I have a small dehumidifier I can put in the tent but can't find the power cord. I must have 100 power cords lying around and none go to this dehumidifier.

Today's Photos:

:peace: :passitleft:

Fuzzy Duck

Well-Known Member
This is a good time to catch up with journals with several journals now in flower :green_heart:

Oh by the way I hope you are doing a review on those airpots & always good to see a fellow growing using them.

I think GSC is living up to the strains name, who baked those cookies they taste good... but with every chef has their own style.

I'm pretty sure we are seeing some phenotype occurrence with GSC which seems to be a few.

Brett Blaze

Well-Known Member
Daily Update -

Stage - Flower Day 32 - 83 days above ground
#1 Bloom Day 15
#2 Bloom Day 20

Last night I did a partial flush of both plants to reduce the high output ppm issue. I decided not to use the Flora Kleen just yet and just reduce the input solution to 50% and flushed with twice the normal quantity. After 15 minutes I fertigated with normal quantity but also at 50% strength. The next fertigation at 3:00 AM was a normal concentration with some decent runoff. This morning the reading were still a little high so they got a partial flush again. I have one leaf on #2 showing some possible Ca/Mg deficiency. This could all be symptoms of some lock out related to the high output ppm. It's not real bad and only on one leaf. The burned tips are on all the leaves.

Last Readings from Yesterday's Fertigation: Input 1465 ppm.

Output #1 1830 ppm (365 over) #2 1875 ppm (410 over).

Last Nights Partial Flush: After partial Flush at 50% solution strength. 765 ppm

Output #1 1575 ppm (110 over normal input ppm) #2 1545 ppm (80 over normal input ppm).

This Morning's readings from 3:00 Normal Fertigation: Input 1465 ppm.

Output #1 1771 ppm (306 over) #2 1638 ppm (173 over).

This Morning's readings 9:00 AM: Partial Flush at 50% solution strength. 785 ppm

Output #1 1586 ppm (121 over normal input ppm) #2 1500 ppm (135 over normal input ppm).

I will do a normal fertigation at 9:00 PM this evening (lights on)

I also started seeing some more gnats. I had a few maybe 5 total before and now I can see several hopping around. Gnats can be numerous in the desert. Since I normally grow in Hydro (non coco) this is the first time I have ever seen any pests. At this stage in the lifecycle both plants shouldn't be affected and the adult numbers are still pretty small. Gnats will lay eggs in the soil and the larva can damage the roots of younger plants.

Thankfully our sponsor @Sierra Natural Science provided me a bottle of SNS 209 I was able to tackle the issue quickly. After the first 50% flush this morning I soak the medium with a liter each of treated water.. I put 4 ml in a half gallon of PH corrected water and applied to the medium of each plant. After 15 minutes I did the final partial flush. @Sierra Natural Science provided me with a gallon so based on the small quantity needed (8 ml per gallon) I have 473 applications still available. I have some yellow strips to see how well it treated the problem.

Today's Photos:

Possible Ca/Mg issue


:peace: :passitleft:

Brett Blaze

Well-Known Member
Daily Update -

Stage - Flower Day 33 - 84 days above ground
#1 Bloom Day 16
#2 Bloom Day 21

I did normal fertigation last night with good outputs using a 3 minute timer. The same 3 minutes produced no runoff at all at 3:00 AM which can really cause problems. I am considering either over fertigating at 3:00 AM to insure runoff and just hand water the other two periods. Trying to get consistent auto watering just isn't working.

Both plants got a pruning last night with more emphasis on #1. The center area was getting too thick restricting airflow. Some small lower branches were removed along with lower and large fan leaves.

The SNS 209 from @Sierra Natural Science worked perfectly. The yellow strips last night and this morning showed zero gnats. It was really easy to apply and affordable. I simply put a small amount in PH corrected water and ran it through the medium until I got runoff. No more gnats.

Both ladies are looking great and I think #2 is getting some color back since I flushed. After looking at some pruned leaves in natural light the color appeared much better than under the LED lights. Looking at them you would think they were different strains. #1 is darker, narrower leaf fingers. shorter and stacks differently while #2 is a lighter green, only a few inches taller but when looking at how the buds are forming #2 seems to be stacking thicker.

Today's Photos:

:peace: :passitleft:


Member of the Month: Sept 2021 - Grow Journal of the Month: July 2022
Your method of growing seems really fussy. Your plants are gorgeous so I know it's working but don't you ever get tired of monitoring them so closely?
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