Cannot figure out cause of rapid ph drop

I've been growing dwc for a year and the whole time pretty much I always have rapid ph drop. Especially in flower I am talking about going from 5.9 to 4.6 in 24 hours. Water temps range from 65-72* I have tried running pondzyme, aquashield, heisenberg tea... My roots are white and have good growth, big plants that grow fast. There are plenty of air bubbles and no light gets into the buckets.

I use 110ppm tap water with dynagro grow and bloom. I have tried with and without tap water conditioner, with and without pro-tekt... I have ran hydroplex pk booster, kool bloom dry, cal/mag, GH ph up, Technaflora ph up; nothing makes a difference. Even at 400ppm my ppm rises and ph dives. I have used hydroton and rockwool and now just use neoprene collars with no media. The larger the rootball the more this happens. My smaller plants seem to stabalize after a few days. The only consistent thing is I feed light... usually around 300 in veg and 500-600 in full bloom.

I have a lot of root pieces breaking off in the buckets so I have to scoop them out with a fish net every few days. I don't know if this is normal with what seems to be good healthy white rootball. I know people go weeks without changing the buckets.. there is no way in hell I could do that because of ph drop and root bits everywhere and what looks like general sludge/shit gathering on the bottom over time.

Sometimes in veg my ph is normal and drifts up a couple ticks over a day... but once they get big it's constant ph dive. I was sure I needed more bennies and the aquashield wasn't enough... but even after inoculation with high doses of tea there is no difference. I have searched and googled and all that shit I don't know how many times over the past year. At this point the only guess I have is it is not getting enough K because it has used it all up, which could be causing it to suck all the small amounts of K out of the ph up causing my ph to go back down. I do not have protekt (potassium silicate) at the moment. They look more stretchy than normal, which I read is one of the signs of K deficiency... among a whole list of other possible causes. That tall ass lemon haze in the back must have a good 5 inches between nodes. Running 800w of HID about 8-12 inches away so that's not an issue.

Other than that I'm out of ideas and have just been adjusting ph to mid 6s. The pic of the roots is 3 or 4 weeks old but they look the same, just bigger. You can see a lot of pieces of root in the res in this pic. The other shit is just fishing line for support.

week 2 flower

First thing i would say is try a different nute and see what happens.

The past 2 weeks I have been using sample of gh flora 3 part because I need to switch to bloom nutes and my dg bloom had massive crystal deposits after storing for 3 months since the last grow. The ph drop is the same or slightly worse with gh flora. The runoff from the hempy buckets comes out at 5.8 using the same koolaid. I do not like the gh 3 part because it is too diluted and I do not need my base nutes seperated out like that.

As of today i am planning on running higher ppm when i change my res tonight, and debating on getting new bottle of dg protekt and bloom or trying pure blend pro bloom and silica blast. I do not feel like changing nutes will fix the issue because many people use dg because of the reported excellent ph stability. I'm not a fan of the salts falling out though.

Ok, i had a thought again. I have tried different silicon additives and some will raise ph and some will lower ph. Does the pro tect raise or lower? If it raises and the plants are taking it up that could be a factor because the pH would lower as its taken.

Pro-Tekt raises pH. I think your pH dropping is normal, I've had the same thing happen when I use Dyna-Gro. Just a few drops of pH up for me and everything was fine.

Yea, it raises ph but I haven't been using protekt this grow so far. My guess is the plants took all the K out of my nutes and now it's taking the K out of my ph up. Since the potassium hydroxide is what raises my ph, if the plant is eating it all, well...

Anyway, that's my guess. I am also going to discontinue using tap water conditioner... With chloramine it breaks down the chlorine and leaves behind ammonia. I have no idea what kind of ammonia or what the ph of it is (plain ammonia is like 11.6 according to wiki but all kinds of shit can change that), so I am just going to stop using it. This also means I need to brew more tea because Aquashield alone does not work for me in my untreated chlorinated tap water.

Thanks for the help; I'll update the thread with how I stabilized the ph if I'm able to.

Imaulle said:

Pro-Tekt raises pH. I think your pH dropping is normal, I've had the same thing happen when I use Dyna-Gro. Just a few drops of pH up for me and everything was fine.

Click to expand...

PH dropping or raising is not normal in large increments.

I still haven't changed my res like I said I was going to do. I'm out of dg bloom and gh flora bloom sample so I'm just going to wait until mon night when I get paid.

So this morning thinking about the K shit I was looking through my old stuff I don't use anymore.... I added about 50 ppm of hydroplex 0-10-6. Just checked the ph 14.5 hours later and it hasn't moved. This is a good early sign.

I also noticed my ppm rose from 350 to 420 ppm over the last 3 days or so. This tells me it is possible the plants are eating K heavily... or at least more than I was supplying at my usual low ppm. So it starts eating my ph up which is potassium which makes my ph drop which locks out nutrients which the plant then drinks more water than it does nutes because they are locked out which then raises my ppm.

Or I could be completely wrong... I'm fuckin sober.

Hydroplex drastically lowers ph.

I topped up with plain water which set ph to 6.0 and 6.2

I only did 2 buckets to see if any difference. Last I checked the ph is still dropping but much slower on the buckets with Hydroplex. 50ppm of bloom booster may not be enough to make the ph stop dropping, but basically I'm not getting shit accomplished until I can pick up some nutes Monday. Hydroplex was the only "nutes" I really had besides dg grow and koolboom dry and I wanted to add some K to see if it makes a diff. I plan to get more DG Bloom and Protekt and run 600ppm on my largest granddaddy purple and see how that goes.

You'll probably have to r/o your tap water if at all possible. I've had issues like this every time I use tap or well water. I've had city water be fine one side of town and dangerously toxic water on the opposite side. Water in Cali's central valley actually almost killed my babies. The water most likely has something in it effecting the balance in your ferties. Perhaps just try running one bucket with r/o from some source and see if that helps compared to other with tap.

Its sick how simlilar our rigs are... dwc, SLH, DG, etc.

And the same issue. lol but, its not fuckin with the kids so I've just adjusted and moved on. using equal parts of Up and Protekt to cut back on the Up dosage.

Things I've kicked out:
-wether RO or Tap, it still happens
-wether straight DG, or DG and additives, still happens
-cold temps, warm temps, still happens
-hydroton has been thoroughly washed, several times, still happens..

nutes used/tested:
-DG Gro
-DG Bloom
-DG Protekt
-EWC Tea
-Bot. Cal/Mag+
-Hum. Honey
-Bio's Ful-Power

No difference, still happens.

hate to say it, but I DO genuinely think it lies in the DG... does that mean im gonna stop using it.... mehhhh.... it IS the most concentrated shit on the shelf.

And maybe you're right, it may be how certain nutes (k included) are available in DG's regime, so uptake causes the swing.

But 6.0 to 4.0 from one nutrinet is a bit farfetched,

the ONLY time it settles out: that I've seen

-first 1 days into a res change
-after about 10-14 days of the same nutes (thinking the base ppm's rise from the Up and Protekt, steadying things out?)

Good luck Mal, and keep me posted.

If it happens in R/O as well. I'd probably move away from DG fertie. I wouldn't think it is worth the hassles, when there are plenty of ferties that don't do this sort of thing.

I don't know if it's DG... could be. But the last 3 weeks I was using GH Flora and having the same problem. More likely, it's something wrong with my water/setup or something I'm doing wrong.

Mon night I bought new DG Bloom and pro-tekt, cal/mag, and ph down. I made new buckets with 110ppm tap water, 25ml pro-tekt, let sit for 10 minutes. Then I added Bloom, cal/mag, tea, at 800ppm and let sit for an hour. Then I came back and adjusted ph from 7 to 5.8

24 hours later the ph drifted up to 6.3, added another dose of tea because the tap water was not dechlorinated or anything. Did not touch ph.

12 hours later the ph drifted down to 6.1

At this point I fully expect a big ph dick in the ass to ensue as normal and have to ph up the shit every day until it magically stops at some random point 15 days in the future. The amount of daily work with a 5x3 tent stuffed full of plants and trying to work in a fuckin thicket is getting truly ball busting having to make such a drastic change in ph every day. Last night it took me an hour to do basic maintenance shit and change my cloner water... I get pretty fuckin ripped working on my plants and leaning over my garden and reaching through the forest of tops and squeezing between the lights and canopy it's a good fuckin thing I have good balance. One of these days I'm going to fuck up and my hand is going to slip and I'm going to bust my ass in the tent... that is beyond the scope of this conversation though

Been there, done that. while doing my ninja acrobatic moves in my flower room to reach one in the back i slipped and landed across a rail setup.

nothing like a bruised rib for 6 weeks or a fucked up crop for 6 weeks.

Yeah, i lost 2/3 of 2 plants & half of another. Expensive fall. But that problem is soon to be eliminated, i am almost doubling my flower room. Preparations began today, construction next week.

I just couldn't imagine my ph being so unstable i had to adjust ph every day or twice a day. my res's go up to 21 days and i go 4-5 days between checking.