PPM staying steady, but rez will drop from 5.7 to 5.2 DWC EXPERT HELP

This never really happens to me as I have been doing DWC for years. PPM stays steady or goes up made 25 points overnight, which is normal. However PH will drop from 5.7 to around 5.0-5.2. I don't get it, both rez's are on day 40 of flower and plants look good... Experts help please... Should I just change the rez's out???

bump

I have the same problem but with ebb & flow with lava rocks.

Usually when ppm goes up it means the solution is too strong and when it goes down its too weak. If it stays the same it is just right where they want it. Is your water level dropping at all? If your ppms ar stable and ph is dropping and water level is dropping I would either do a res change or whats your EC? If below 1.0 add more if higher than a EC of 1.4 drop it towards a EC of 1.0

^^^^ wouldnt his EC change with that swing?

How are your roots?

not necessarily only if the plant wasnt liking what it was getting... ALso seen ph constant go down when something up with the roots

I suggest you drop the ppm by 100 from wherever it was. But a new fresh nutrient solution not just topped up.

Johnei said:

I suggest you drop the ppm by 100 from wherever it was. But a new fresh nutrient solution not just topped up.

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This^

Cut back your EC a little, appx. .1-.2EC. You should start to notice the EC will still stay stable, but PH should slightly rise over time, which is what you're looking for. Usually around 45-50 day's I notice most strains nutrient uptake starts tapering off fairly quickly.

Brabb said:

not necessarily only if the plant wasnt liking what it was getting... ALso seen ph constant go down when something up with the roots

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I see that as well, the first thing I check is root health when PH drops. I also use that as a guage to change res. if the PH drops in the span of a day or two I will drain and refill, typically 5-7 days in full flower. I do see that if EC is rising drastically it will also effect PH and will drop it to a lower level. And yup I have found that no higher than 1.2ish is the sweet spot, although I've had a few hungry ones lol. Also it took me a bit to find a nutrient line that was PH stable in my highly buffered well water lol.

when pH rises and EC drops, it is because the plant is feeding removing a portion of that nuitrient EC you are measuring, and is telling you that you can up the nutrient EC by THAT much. Nutrients are acidic, as foods are taken out the pH will rise.

The best place to be is when the pH is ever so slightly rising each passing day while the water is dropping it's level and EC is staying steady, this means they are eating perfectly what they need at that moment. EC stays steady while water level drops and pH very close to stable but rising slowly each day.

If the EC is rising and pH is dropping, its because, nutrients are acidic, and as the solution becomes stronger EC showing the plant is spitting it out not eating it and only wants the water from the tank, there's too much nutrients in there and it doesn't want or need it, the pH will drop as EC rises along with the acidity as the plants dont need that much nutrients at that time and you need to lower the EC by THAT much.

Your plants are always talking to you, you need to learn to listen to them better.

Good Growing.

Or your roots are sick as stated .

Budley Doright said:

Or your roots are sick as stated .

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Yep

Budley Doright said:

Or your roots are sick as stated .

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I've come to my own conclusion through trial and error and reading many, many posts about root problems and they all seem to have a common factor, excessive EC. Over feeding provides extra food for bacteria, at the same time slowing the plants uptake(nute burn/ lockout), which can cause root die off, creating more food for bacteria. It's a vicious cycle. Everyone wants to start feeding their plants ASAP, when it's not usually needed, and generally too much.

Simply dropping ECs removes this excess food source, allows the plants to resume full potential, which in turn uptake more nutrients, relative to the stronger EC from before, removing even more food sources for root bacteria.

Keeping the res clean, ie: no dead leaves or excess dead root material and not providing a nutrient buffet for bacteria, along with bene bacteria dosing, have kept me root problem free for close to 2 years. And I regularly saw mid 70 res temps in the summer.

Ya gotta figure, there's outdoor commercial growers running DWC, RDWC, Dutch buckets, etc who's res's are @ambient outdoor temps and they don't lose everything to rot pathogens constantly.

I'm sure running high temps can be done but O2 becomes the deciding factor. If you can keep DO levels up running at higher temps you should be good, I can't so I chill lol.

I do both - well, all... Sterile rez/chill and beneficial bacteria - different systems.

I veg in 8, 5 gal DWC buckets. My first crack at it wound up with horrible root rot and I learned some expensive lessons. But learn I did. I also flower in a 6 plant Under Current RDWC.

My problems in the beginning were:
- too much nutes (mixing to manufacturer's guide)
- high temp
- no bennies OR disinfectant

Then I went sterile rez using UC Roots which is what I'm currently still doing in my RDWC. But, I did a comparison to test out Hydroguard and ran 4 buckets with it and 4 with UC roots and just allowed the buckets temps to do whatever they wanted they ranged from the mid 70's up to the low 80's or more. To further stress test it, I didn't change the rez's at all - just topped with fresh nutes or RO as needed. End result - all 8 plants did great - no problems whatsoever.

I'll probably go to beneficials in the RDWC too too

FennarioMike said:

I do both - well, all... Sterile rez/chill and beneficial bacteria - different systems.

I veg in 8, 5 gal DWC buckets. My first crack at it wound up with horrible root rot and I learned some expensive lessons. But learn I did. I also flower in a 6 plant Under Current RDWC.

My problems in the beginning were:
- too much nutes (mixing to manufacturer's guide)
- high temp
- no bennies OR disinfectant

Then I went sterile rez using UC Roots which is what I'm currently still doing in my RDWC. But, I did a comparison to test out Hydroguard and ran 4 buckets with it and 4 with UC roots and just allowed the buckets temps to do whatever they wanted they ranged from the mid 70's up to the low 80's or more. To further stress test it, I didn't change the rez's at all - just topped with fresh nutes or RO as needed. End result - all 8 plants did great - no problems whatsoever.

I'll probably go to beneficials in the RDWC too too

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I ran and loved hydro guard but I can't get it here anymore. I switched to chilled water while still using hydroguard and was frankly a bit worried to go without anything but the roots did well, still trying to find a good replacement for hydroguard but haven't found one yet that didn't turn everything black lol.

I've found that too much phosphorus in they nutrient solution can push pH down. Might have something to do with it.