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- #141
Delps 8 Hydro RDWC Gelato Autoflower 2021
- Thread starter Delps8
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Yes, try to keep it within range of 5.9 - keeping in mind that you are able to see much more detail of the activity than most growers - and refrain from acting too quickly.
Unless you have a bacterial infection - which will drive the pH down - what you are seeing is natural feeding - right now, cations are the preferred meal.
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- #144
Delps8
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5.9 - will do.
Re. “keeping in mind…” - that has to be the most polite way anyone has ever said “chill the f out”.
Thank you.
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- #145
Delps8
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I understand, in the very basic sense, how that process leads to pH dropping. What I don’t understand is the advice that if pH drops, the appropriate action is to reduce TDS. Can you shed some light that?
I’ve attached two documents which I refer to as “Wonder Chart” and “Son of Wonder Chart”. The latter is from a cannabis site in the UK, the other is text that was scraped from a posting in 2012. I’m drawn to them because they’re very much “If…else…End if” which is my stock in trade as a programmer. I’m not avoiding the intellectual challenge of learning about nutes at the cation and anion level - I’m looking forward to it, in fact.
My confusion is - why do these two sets of quite similar advice veer away from the sage advice that you’ve provided?
I cannot. It flys in the face of what I understand and have experienced with hydroponic reservoirs. There is no reason to lower the ppm when the pH drops.
Instead, simply replace water as needed - which will itself lower the ppm (and in my case - since my tap water pH is above 8 - the pH comes back up also). Just keep the pH as close to 5.8 - 5.9 as you can. After doing this a few times, the reservoir ppm reaches a point low enough that you feel it might be out-of-balance - replace the reservoir with a fresh higher ppm nutrient solution.
What you will notice about pH is that it tends to rise during veg into stretch - as the plant takes in more nitrate than anything else - releasing more OH- than H+
During flowering, the plant ramps up uptake of K+ and this results in the pH going down.
Those charts are guidelines and, just like the ubiquitous charts showing pH ranges for various nutrients, very derivative of information which isn’t set in stone.
During flowering, the plant ramps up uptake of K+ and this results in the pH going down.
Those charts are guidelines and, just like the ubiquitous charts showing pH ranges for various nutrients, very derivative of information which isn’t set in stone.
Back again
Well, it’s too late to add this to my last post, but I thought you might be interested in a DWC grow by one of the greats on 420. Notice that the pH has been dropping for the last week or so.
Post in thread '420’s Perfect Sun Led Goliath V2 Sponsor Grow Purple Punch Clones Hydro Flood & Drain'
420’s Perfect Sun Led Goliath V2 Sponsor Grow Purple Punch Clones Hydro Flood & Drain
Well, it’s too late to add this to my last post, but I thought you might be interested in a DWC grow by one of the greats on 420. Notice that the pH has been dropping for the last week or so.
Post in thread '420’s Perfect Sun Led Goliath V2 Sponsor Grow Purple Punch Clones Hydro Flood & Drain'
420’s Perfect Sun Led Goliath V2 Sponsor Grow Purple Punch Clones Hydro Flood & Drain
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- #149
Delps8
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Over two grows, I've spent a shitload of time gradually dropping TDS in hopes of stopping pH from falling so I'm relieved that I don't have to go through that again.
I've been following that approach yesterday and today and thing are going very well. pH is dropping but only slowly.
Water uptake is 0.8 gallons between 1100 and 2038. That's a huge amount of water but the plants look incredible and I attribute that to your advice
Some of the leaf tips on Jeff were damaged but that's as far as it got. There were some areas on Mary (the largest plant, on the left) that had inter veinal chlorisis and there were some tan spots from Ca deficiency. They might still be there but there's so much lush, green, new growth that I can't see those old leaves anymore!
The turn around has been phenomenal. Even they're happy - they agreed to let me take a family portrait!
Amazing variance within one batch - that's one plant on the left half, one in the right center, and one in the back. Definitely not clones!
I'll top off with RO and swap the res in the middle of the week.
Now I need to reset the lights and do some LST and defol.
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- #150
Delps8
Well-Known Member
So this is an expected response to plants going into flower. That's helpful to know. Thank you.
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- #151
Delps8
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I appreciate the link. I'll check it out.
That light is very close - is it still the T5?
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- #153
Delps8
Well-Known Member
At times, pH was dropping 0.1 units every 90± minutes. After switching to the formula that you provided, it's now 0.1 units every 180± minutes. EC, per the monitor, it 0.76 (380/5300) but I haven't checked it with the Bluelab pen. The monitor was 25 PPM high when I calibrated it vs the pen which was 0± PPM.
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- #154
Delps8
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No, it's the Growcraft X3 at 43%. I've allowed the plants to grow into the light because I wanted to determine the PPFD when they start praying. I found it.
Moving the light up is a task for today as well as defoliation mainly to clean up Mary and Winnie whose canopies are incredibly dense. There's a 6" fan on tent left and two small fans on top of the res, aimed under the leaves and I started up the dehu so the garage is at 43% RH vs 76% outdoors. The dehu makes it a lot easier to keep RH in check in the tent but the Infinity runs quite a bit.
Re. the light - I used the T5 in concert with the Mars SP3000 for the early stages of veg and then switched to the X3. My rationale for that approach is that the T5 is almost all blue and green light, the Mars has a high % of blue whereas the X3 is the "full spectrum" version of the light rather than their veg version. The plants ended up being very short and compact.
Some time ago, I checked out ppfdcharts.com and I took one set of their readings of the X3 - just the centerline readings - and plotted the data. Per the attachments, there's an interesting curve in uniformity as hang height increases. The green text indicates the level of the uniformity. The net pots are located 12" left, 4" left, 4" right, and 12" right of center. At 6" hang height the light is amazingly even - the measurement that throws it off is the PPFD at 12 RL. As hang height increases, uniformity decreases but the curve slopes back down after 12" and gets more even as hang height increases.
These are only the centerline readings which was all I needed at the time because the plants were seedlings. I contacted the site, explained what I wanted to do with their data, and asked them to send me a copy of all of the data for the X3. The charts are images vs being rendered as tables so that was the easiest way to get the bulk data. Unfortunately, I have yet to receive a response. I'm not keen on typing in hundreds of data points but it would make a very interesting 3D graph. My next best step is to use the data from the manufacturer but they supply only 4 sets of PPFD data.
The recommended hang height is 12" to 24" but, if the centerline data are representative of the light over all, the 20" or 22" heights look to be the best tradeoff of uniformity vs energy consumption. ATM, the light is running at 143 watts and the light was on for 19 hours yesterday.
Per the third attachment, that gives me a DLI of 40 which is very high but, looking at the plants, they're responding well. I take PPFD readings at the back, center, and front of the plants. That gives me some insight into just how much light they're getting and, implicitly, how what I need to do to make the canopy "level". My last grow as a disaster - the plants were 24", 30", and two at 40" because I did nothing to LST them. Different approach this time.
Looking at values in the two sets of readings (one with Jeff, one without), I chose to use the average value for DLI calculations with the idea that to do the best I can to get the canopy uniform and level. Jeff is parked in the back right corner which is a PITA because corners have the most light falloff and Jeff is the shortest plant. I suppose I could move Winnie and Jeff around but that hasn't been at the top of my list - the far more pressing issue has been to keep them from dying!
OK, off to the tent where my action items for today are "Defol and raise the light".
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- #155
Delps8
Well-Known Member
"Back again
Well, it’s too late to add this to my last post, but I thought you might be interested in a DWC grow by one of the greats on 420. Notice that the pH has been dropping for the last week or so."
I read the entire thread last night. Very illuminating. For many weeks, pH responded in the expected manner and, then, boom! The fun and games start. What's interesting is that there are so many conversations about "pH is falling - what should I do?". Based on we're seeing with my story unfolding, it seems like your approach, based on very valid science, is that this is a completely natural and expected reaction…no, it's a completely natural and expected behavior. No argument from me. I was headed down the rabbit hole if @Rexer hadn't called you in to walk me back from the ledge.
That light that he's using is a beast but I suspect that it's the experience and expertise of @West Hippie that's making things really "shine". I've subscribed to that journal and will probably read it again. Thank you for recommending it to me.
Well, it’s too late to add this to my last post, but I thought you might be interested in a DWC grow by one of the greats on 420. Notice that the pH has been dropping for the last week or so."
I read the entire thread last night. Very illuminating. For many weeks, pH responded in the expected manner and, then, boom! The fun and games start. What's interesting is that there are so many conversations about "pH is falling - what should I do?". Based on we're seeing with my story unfolding, it seems like your approach, based on very valid science, is that this is a completely natural and expected reaction…no, it's a completely natural and expected behavior. No argument from me. I was headed down the rabbit hole if @Rexer hadn't called you in to walk me back from the ledge.
That light that he's using is a beast but I suspect that it's the experience and expertise of @West Hippie that's making things really "shine". I've subscribed to that journal and will probably read it again. Thank you for recommending it to me.
You’re on track now - happy, happy, joy, joy! 
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- #157
Delps8
Well-Known Member
I'm really hoping that's the case. This has not been easy.You’re on track now - happy, happy, joy, joy!
TDS has been stable for a few days. Water uptake is a little over a gallon in 26 hours.
Thank you for that but I wished I knew the science you know . I was conditioned by the ANutrients the ph perfect, kind of made me expect that all nutrients should work as it did . Made me a believer for the hydro bible and then I change nutrients. It put me into another world of growing with the cheap nutrients. I wished I could have helped like Felipe did . I always try to protect the roots, as the saying goes the bigger the roots the bigger the girls ."Back again
Well, it’s too late to add this to my last post, but I thought you might be interested in a DWC grow by one of the greats on 420. Notice that the pH has been dropping for the last week or so."
I read the entire thread last night. Very illuminating. For many weeks, pH responded in the expected manner and, then, boom! The fun and games start. What's interesting is that there are so many conversations about "pH is falling - what should I do?". Based on we're seeing with my story unfolding, it seems like your approach, based on very valid science, is that this is a completely natural and expected reaction…no, it's a completely natural and expected behavior. No argument from me. I was headed down the rabbit hole if @Rexer hadn't called you in to walk me back from the ledge.
That light that he's using is a beast but I suspect that it's the experience and expertise of @West Hippie that's making things really "shine". I've subscribed to that journal and will probably read it again. Thank you for recommending it to me.
As you see I have some great input into the journal, without them I’d be lost . When I got to 420 I never checked the ph because of the ph perfect nutrients I just top her off and off I went . I even went by the days the seeds had on them in flower. I was lucky because they all were great smoke without looking at trichs.
I thank you for reading my thread and your response to the ph I’ll keep working with it .
Like I did say in the post about the light it still stands I wished everyone here at 420 could have a @Perfect Sun LED Goliath V2 in there grow room it’s awesome.
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- #159
Delps8
Well-Known Member
Probably a good idea to adjust the lighting…
The DLI calculations are based on the average. One part of Mary is receiving > 1000µmols.
I super cropped a few of Jeff's stalks last night because they were just a few inches from the light. Had I not done so, that 470 reading would have been much closer to the 1030 that Mary is getting.
The DLI calculations are based on the average. One part of Mary is receiving > 1000µmols.
I super cropped a few of Jeff's stalks last night because they were just a few inches from the light. Had I not done so, that 470 reading would have been much closer to the 1030 that Mary is getting.
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- #160
Delps8
Well-Known Member
Ah ha, that’s why you recommended Z7, right? I added that a few days ago. How often do you add it to your res?
Re. chemistry - that’s magic from @FelipeBlu. The chemistry piece is was very helpful (make that immensely helpful) but the other huge factor was that he helped me understand that dropping pH is a natural phenomenon. Like you, I latched on to the “hydro bible” but I was flying IFR right into 0 PPM’s. That’s where experience and knowledge stepped in. What a friggin’ difference!
I looked at using AN. Sounds like they worked really well for you. I’ll keep that in mind for my next grow.
Yeh, that’s a beast of a light and your grow looks incredible. Keep it up!