Another kick at the can.

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airedog

airedog

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Taken April 26 (Day 23 from flip); tops of frames are 5' 6" off the floor. Stretch seems to have stopped and they are stacking nicely and there is a distinct cherry aroma in the grow area.



April 26.jpg
 
airedog

airedog

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Day 26 from flip and the dreaded RDWC mid-flower pH plummet is starting to happen.

I'm mitigating the effect of the drop by using pH Perfect base nutes as the chelation means a wider pH range in which the nutes are available; i start to worry when i hit the 4s and change-out at 4.0 (although i've seen it hit 3.8 in past grows). This past week the pH started drifting down to 5.1 by Wednesday night and then plummeted by another 0.6 to 4.5 by end of ON cycle yesterday morning. My plants have been drinking about 7 gallons of top-up nutes per ON and they really like their CalMag. Yesterday though i took a chance after looking at what Aqua Man and BioMaster have said on the topic and added in more base nutes to both my system and the top-up. An hour later the system had gone from 1360 ppm @ 4.5 pH to 1460 ppm @ 4.8. The top-up got a stronger shot of base nutes and by end of ON cycle this morning nute strength was 1500 and pH is at 5.0. I'm due to change-out tomorrow so i just refilled top-up with RO water and strength should drop down a bit by tomorrow morning.

Tomorrow i'll change-out with lower strength nutes in order to leave headroom if i need to try and bump pH levels up and hopefully extend the time till change-out. I'm trying to keep RH in low 40s and my ON temps rise into the low 80s, with OFF temps low to mid 70s due to added heat from dehuey.
 
smokedareefer

smokedareefer

Day 26 from flip and the dreaded RDWC mid-flower pH plummet is starting to happen.

I'm mitigating the effect of the drop by using pH Perfect base nutes as the chelation means a wider pH range in which the nutes are available; i start to worry when i hit the 4s and change-out at 4.0 (although i've seen it hit 3.8 in past grows). This past week the pH started drifting down to 5.1 by Wednesday night and then plummeted by another 0.6 to 4.5 by end of ON cycle yesterday morning. My plants have been drinking about 7 gallons of top-up nutes per ON and they really like their CalMag. Yesterday though i took a chance after looking at what Aqua Man and BioMaster have said on the topic and added in more base nutes to both my system and the top-up. An hour later the system had gone from 1360 ppm @ 4.5 pH to 1460 ppm @ 4.8. The top-up got a stronger shot of base nutes and by end of ON cycle this morning nute strength was 1500 and pH is at 5.0. I'm due to change-out tomorrow so i just refilled top-up with RO water and strength should drop down a bit by tomorrow morning.

Tomorrow i'll change-out with lower strength nutes in order to leave headroom if i need to try and bump pH levels up and hopefully extend the time till change-out. I'm trying to keep RH in low 40s and my ON temps rise into the low 80s, with OFF temps low to mid 70s due to added heat from dehuey.
Im always amazed when people talk about ppm @ 1200,1300.

Here i am at day 32 flower and im pushing them @ 500ppm
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20201114_120044.jpg
 
airedog

airedog

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After change-out pH continued to drop drastically so i took a look through the access ports and saw some of the root rot taking hold again. Changed-out, minus Nirvana, doubled down on HydroGuard as well as running a L of HydroGuard/SensiZym solution through the netpots. I also adjusted my float valve to drop solution levels in system. Added in some H & G pH Stabiliser/Optimizer and pH drop has slowed down, Plants are drinking and cherry smell is noticeable in grow area. Currently nute strength is 1120, pH is 5.7 and solution temp is 67°. I'm continuing with the drench. Time will tell if i can stop the developing root issues enough to determine whether or not that H & G pH stabilizer will remedy a problem that seems to run rampant in mid to late flowering RDWC systems. I can remember threads regarding this at Overgrow back in 2003/4 (anyone else remember Dr. Dragonfly or Jamesgang?). There are a few threads here (and most other forums) that discuss the subject as well.
 
airedog

airedog

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Day 43 and buds are packing on weight, put plant yoyos on quite a few secondary branches. pH drop continues to be a problem but is under control with the addition of potassium bicarbonate (thank-you Aqua Man). I feel that this is going to go 8 weeks and have been feeding as such, so they got Overdrive last week and this; and i'll likely change out nutes mid-week in order to get back to a more balanced nutrient solution due to heavy uptake of potassium. Nutes last week were running 650 - 720 ppm with pH running from 4.3 to 6.5; pH Perfect formula helps but only to a point. I've kept my nutes down around 67F and running heavy bennies and SensiZym. Depending on how trichomes look at the end of the week i'm hoping to start flushing with Flawless Finish at next Saturday's change out; i'll likely do a 2nd change out with Flawless Finish and then at least one more with just RO water.
 
airedog

airedog

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Coming up on the end of Week 7 and i've done a mid-week changeout as pH keeps dropping quickly. Root issues seem to be under control but plants are sucking down the potassium as quickly as they can; drinking about a quarter of system capacity per day. Currently i'm running between 450 - 550 ppm and pH drifts from 6.4 down to mid 4s; nute base is pH Perfect Conny from AN. I'm also using Microbial Mass Pro or HydroGuard along with SensiZym to keep root issues in check. Up till now i've used H & G pH Optimizer to initially stabilize pH, adding potassium bicarbonate when it drops below 5.4; also heavily supplementing with AN Overdrive (big K booster) so buds are dense. At this point i'm feeding Conny, bennies, B52, SensiZym, Overdrive, potassium bicarbonate, and Bud Factor X; heavy on the Overdrive and other K sources.

MA 20.jpg


MA20 RR top.jpg


MA20 smaller bud.jpg


MA20 K drop.jpg


Can't use carbs in RDWC and i think that's kept colas and buds fairly small, i'll try an outdoor plant in soil and use an AN Iguana Juice base and mostly organic supplements other than Bud Factor X, hopefully it will be a normal summer and the plants will finish quickly before autumn rain.

Many thanks to those who have helped me get to this point.
 
airedog

airedog

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I've been hitting them pretty hard with Overdrive and potassium bicarbonate and feel that my ratios are probably way out of whack, so i did a change out today. Leaned a tad more on the B than the A, added in B52; Overdrive; Bud Factor X; SensiZym and HydroGuard, all at reduced doses. While i have a slick on the top of the epi there is no film on the float valve nor is there a smell so i believe it's bacteria die-off as opposed to root issues. Potassium bicarbonate has been working well for keeping pH relatively stable and i've stayed between 5.4 - 6.0 for the most part, aiming to keep solution strength between 400 and 500. Strength has gone to 550 and pH 6.0 right after adding potassium bicarbonate but it usually drops into the zone within a few hours.

We're having damp, hot weather and it's been difficult to keep temperatures under 80 during ON cycle, so terpenes are taking a hit. RH is running mid to high 40s and the dehumidifier is definitely contributing to the heat issue. No budget for a mini split so i'll likely try to find a way to use a 14 000 dual hose portable ia already own, next year. I need to find out if i can extend the ducting beyond 5' if i put inline fans on them to accommodate basement windows.
 
smokedareefer

smokedareefer

I've been hitting them pretty hard with Overdrive and potassium bicarbonate and feel that my ratios are probably way out of whack, so i did a change out today. Leaned a tad more on the B than the A, added in B52; Overdrive; Bud Factor X; SensiZym and HydroGuard, all at reduced doses. While i have a slick on the top of the epi there is no film on the float valve nor is there a smell so i believe it's bacteria die-off as opposed to root issues. Potassium bicarbonate has been working well for keeping pH relatively stable and i've stayed between 5.4 - 6.0 for the most part, aiming to keep solution strength between 400 and 500. Strength has gone to 550 and pH 6.0 right after adding potassium bicarbonate but it usually drops into the zone within a few hours.

We're having damp, hot weather and it's been difficult to keep temperatures under 80 during ON cycle, so terpenes are taking a hit. RH is running mid to high 40s and the dehumidifier is definitely contributing to the heat issue. No budget for a mini split so i'll likely try to find a way to use a 14 000 dual hose portable ia already own, next year. I need to find out if i can extend the ducting beyond 5' if i put inline fans on them to accommodate basement windows.
What source are you using for the Potassium bicarbonate, walked out to our grow after reading your post and the ph crash has started here. I'm on day 18 flower. Nutes were at 480 ppm yesterday and 5.8. Readings just now before adding anything were 410ppm and 4.7
 
airedog

airedog

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smokedareefer

smokedareefer

airedog

airedog

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Mixed in RO water and added to epicenter and top-up res to help buffer the solution.
 
smokedareefer

smokedareefer

Mixed in RO water and added to epicenter and top-up res to help buffer the solution.
At what rate? I too am running the same 4 site 13 gal

I doubled up on the nutrients and and bumped them up to 490 ppm, seemed to ease the crash last night. 5.8 to 5.2
 
airedog

airedog

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Start with 0.25 gm/ gallon of solution wait a few hours to see what it stabilizes at and adjust if needed. I mix it into a liter of water and add that to my nutes.
 
airedog

airedog

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Started to flush on Sunday, used Flawless Finish and some potassium bicarbonate to raise pH a bit. This whole grow used lower levels of nutes than i had previously used and from mid-flower on it was about half of what i normally would have fed. Additionally, the tip to use potassium bicarbonate to minimize the dreaded RDWC flower phase pH drop, worked very well. During flush i've been used to watching solution strengt rise while pH dropped and, so far, it's been the opposite. Started out near 200 ppm and pH running 5.8 - 6.0; strength has slowly dropped and pH hit 6.2 then settled at 5.8 yesterday while strength dropped to 120 ppm. This morning it's 110 ppm and 5.6 pH. Plants continue to drink about 6 gallons/day and the fade is progressing with leaves staying supple. I'm aiming for 10 - 14 days and will finish off with a couple of days of just RO water; not sure if i'll do an interim Flawless Finish only changeout.
 
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airedog

airedog

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Changed out today with Flawless Finish and HydroGuard; initially 70 ppm at 5.8 pH and 70F. I'll check in a few hours after it's mixed and stabilized. If all goes well i will switch to just RO water on Sunday and go another 3 - 7 days. Leaves are starting to show a heavy potassium drain and lower ones are bleaching at the tips and starting to crisp. I'll try to get pix at next ON cycle.
 
airedog

airedog

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As if i can't make enough mistakes on my own....

Going this late into spring, in a year of record breaking heat and humidity, i'm having a bitch of a time staying within a half-assed reasonable environmental zone. My house a/c is pushed to the max and struggling, running constantly as do my dehueys. All that and i'm lucky to stay low 80s and 52% RH during ON and 72 and low 40s RH during OFF. Had the HVAC guys in yesterday as furnace blower stopped for a good while and they tuned the a/c as well; moving my dehuey hoses in the process and not placing hose flat on floor at the end. 2 hours into OFF and i was at 72F at 60% RH. Emptied dehuey buckets, placed drain hoses back on ground and within 5 minutes i was at 57% RH and 74F.

No question, i have to add in a mini split and larger dehuey (if budget allows). I'm also going to have to chop a few days sooner than i planned on.
 
airedog

airedog

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They've fattened up nicely and the sugar leaves look a bit better; switching to RO tomorrow and they'll come down sometime before Monday depending on how the trichomes look.


J8 1.jpg


J8 2.jpg
 
airedog

airedog

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Changed out to just RO water Wednesday; initial values were 0 ppm and 6.3 pH. By lights ON it was 30 ppm and 6.4. At lights OFF Thursday morning it was 40 ppm and 6.8 pH. Changed out again and 0 ppm at 6.3. I don't believe it's actually 0 ppm just that it's below 30 ppm; once it drops to below 30 and stays there through an ON/OFF cycle i may give them 24 hours of dark or maybe just chop them, depending on how long it takes to get into the sub-measurement range.

This morning it was back at 40 ppm but pH had topped out at 6.3; drained it all and refilled with RO, tomorrow i'll change out once more and start harvesting Sunday.
 

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