PH rise, EC rise, less water usage

Hi guys,
I'm in the week 3 of flowering and I need some advice.
A few days ago I noticed that my plants started to use less water per day (10% less). This was followed by slightly raised EC by 0,03EC. It was a bit confusing bcs I lowered the humidity and room temperature a day before (from 27 to 26 celsium, from 56 do 50 humidity) - I was expecting the plants will start to use more water bcs of the lowered humidity.

From this point the EC was constantly rising, so I diluted the water in the reservoir by 0,1EC. But the EC rised again over their day light period. So I repeated the dilution every day, until it was -0,35EC from the highest point.

Also I noticed typical nute burn (yellowing leaf tips) and probably potassium deficiency on lower fan leaves (yellowing, dead brown spots, crispy, curling upwards).

I'm flushing them now, but don't wanna make it even worse.

Qs: Why is PH rising, EC rising, but the plants are consuming less water? If I lower the EC to (let's say) 0,9EC, will the EC still rise as the plants need to balance the nutes inside them or not?

P.S.:roots look fine, water temp always 19-22 celsius, PH 5,8-6,1

OK, some news - it definitely is potassium lockout...why? Maybe a two weeks ago I switched my flooding cycles to flood every 2h even during night (switched from 3h during night). Also lowered room temperature and humidity as I wrote above. Soooo...the plants don't appear to be overwatered, but there is a chance that they really are and this is why the potassium lockout appeared.

Does any1 had this issue? Will they recover soon?

what nutes? what additives? what EC are you at now?

Did you switch from a vegetative nutrient solution to flowering nutrient solution? Since we can't see your plants I will guess because I love being wrong.

If your running the wrong solution you could have to high of a few minerals in your mix and to low of potassium for flowering.


Or am I totally wrong?

I am using Advanced Nutrients 3part mix + Big Bud + B-52...the same proportion as AN recommends. Very potassium rich. Already flushed and mixed new reservoir with EC lowered to 0,5...but EC and PH still rising.

I checked (just to be sure) what content of cal/mag contain that 3part formula and found out that there is cal/mag ratio 2,4%/0,1%. As long as I use RO water, this seems to be very low amount of Magnesium as it needs to be something like 2/1 ratio.

Am I wrong or this could be the reason? I added Bud Factor X to reservoir instantly at double ratio as it contains 0,5% magnesium.

Oh gosh, I need to solve this riddle asap.

Without pictures you are making this incredibly difficult. I'm not sure if most but a lot of knowledgeable people won't wven waste their time without one.

Not sure when exactly but it's normal for a flowering plant to start to require lower amounts of ec. My first good grow I had my mix up to 2.4ec and it was going down the whole time. Got to flowering and a few weeks later I had to drop it down to .8ec and it still went up slightly.

As for your ph going up that's just a natural reaction to tranfer of positive and negative ions, it's better then going down. Though I would think as you stated that with a decrease in humidity your water usage should increase. So its almost a two fold issue if you include the two together.

foliage2018 said:

+ Big Bud + B-52.

Click to expand...

ditch the big bud. your 3 pt should have enough p and k.

not sure what b52 is? vitamins? that should be fine to use.

what EC are you at?

and how exactly did you flush?

Ec isnt a specific number to be reached so just keep dropping it till your girls ask for more. I'm of the belief that once you get it low enough it will equalize but that a very uneducated guess from oersonal experience.

foliage2018 said:

I checked (just to be sure) what content of cal/mag contain that 3part formula and found out that there is cal/mag ratio 2,4%/0,1%. As long as I use RO water, this seems to be very low amount of Magnesium as it needs to be something like 2/1 ratio.

Am I wrong or this could be the reason? I added Bud Factor X to reservoir instantly at double ratio as it contains 0,5% magnesium.

Oh gosh, I need to solve this riddle asap.

Click to expand...

It’s the advanced nutrients. I’m using them in soil but if I don’t use it all I leave it in my barrel overnight with bubblers the ph goes way up and ec

I attached few pics. The two last of them are B-52/Big Bud and Micro part of the 3part basic nutes.

EC was downed from 1,5 to 0,45 after a flush. Flush was made by using RO water + flawless finish (as AN recommends).
But I realized one other change I made about 10 days ago. I stopped using Bud Factor X (0,5% mag) and Bud Candy (0,5% mag). This was bcs I was finding the cause of brown sludge on the top of the water level in my res tank. Few days after the plants started to consume less water, PH was rising (plants were not using K) and the EC was rising too.

Palmerrdgrower said:

It’s the advanced nutrients. I’m using them in soil but if I don’t use it all I leave it in my barrel overnight with bubblers the ph goes way up and ec

Click to expand...

OMG, what a crap I bought so called best hydroponic nutes on the market (EU)

foliage2018 said:

I attached few pics. The two last of them are B-52/Big Bud and Micro part of the 3part basic nutes.

EC was downed from 1,5 to 0,45 after a flush. Flush was made by using RO water + flawless finish (as AN recommends).
But I realized one other change I made about 10 days ago. I stopped using Bud Factor X (0,5% mag) and Bud Candy (0,5% mag). This was bcs I was finding the cause of brown sludge on the top of the water level in my res tank. Few days after the plants started to consume less water, PH was rising (plants were not using K) and the EC was rising too.

Click to expand...

And I only use half of what they recommend. I only use big bud 3 weeks into flower

foliage2018 said:

OMG, what a crap I bought so called best hydroponic nutes on the market (EU)

Click to expand...

I use grow micro and bloom for veg and big bud in flower along with them but I guarantee that the ph and ec changes within 2 hrs.24 hrs later ph is 8. From 6 last night in my res

Palmerrdgrower said:

I use grow micro and bloom for veg and big bud in flower along with them but I guarantee that the ph and ec changes within 2 hrs.

Click to expand...

I am trying to keep the proportions of the nutes as it always is 2:1=basic:additives (in the flower period). Actually it's mostly 1/4 strength when you compare it to AN feed chart. But when everything was fine, PH wasn't fluctuating by much. As the EC was falling, PH was rising - that is actually OK. When I was very close to the "sweet spot", the PH wasn't fluctuating at all.

Whens the last time you calibrated your ph meter?

shawnery said:

Whens the last time you calibrated your ph meter?

Click to expand...

Two days ago. And dont forget the "ph perfect solution" in the AN nutes. I also bought a new EC meter few days ago.

I have a very first sign of improvement. EC didn't rise this day.

I need to understand these micro and secondary nutes my plants need and a dosage through the plant's life. Not just using nutrition companies's feedcharts like a blind. Any recommendation, please? (scientific based literature)

Find hydrobuddy and go here to post 6.
https://www.rollitup.org/t/jacks-321-questions.974851/page-5
Don't worry about the main body of the post. On the left side of the chart are the individual nutrient ppm you need for each nutrient during veg and bloom.

I'll help as much as i can with hydrobuddy but I'm still figuring it out as well.

As a MacOS user.... But I noticed that there are always sth like 2:1=cal:mag ratio in that post. And that is quite interesting as you get sth like 3:1 when using AN full nute-line.