Ph in DWC please help

Ok so i did make a dumb move by starting my first grow in a DWC. Im at week 1 of veg plant is gaining size pretty quickly. So im having problems keeping the ph down now i know that ph rises because of the nutrients the plant takes up causes ph to rise but going from 5.8 to 7.0 in a 24 hr period so on the daily im adjusting the ph is this normal? Before i was using ro water but realized it is not stable so i switched to tap and using conditioner to remove chlorine. The plant is growing faster aslo i use eco2 @ 800ppm ive noticed that after a few days the water is also lighter but the ec dont change and my plants new growth is yellowing from stem out idk what this means and since the water was lighter so i added more nutrients at half strength im hoping this fix the defency because the last water change i only added nutrients at half strength so i think i got that but the ph issue is really frustrating. Help from an experienced hydroponic grower would be most beneficial tia also all the stems are green so i see no stress no red. The beginning there was red stems but that was because of the ph and that was then i realized the ph rises on the daily by several points which is disturbing


Cant really see the yellowing because of the light but that is her

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@HappyHydroGrower @NUG61 @CooterJuice can you hydro Bros share some wisdom on PH spikes. My experience with reservoir PH drift has been related to higher temps and not keeping the nutrient solution moving :love_you_gesture:

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Thanks for the tag OG… @Crssmk ,I grew in bubble buckets for over 3 years, having only 3 gallons in the bucket, i too had to chase ph daily. I got use to it as part of the process. Im now in totes with 5gallon in each and the ph is more stable. I have 2 air stones and a little recirculating pump in each to keep it moving. :sunglasses: :peace_symbol: Its not to late to grab a couple totes cut a hole in the top and set your net baskets in.

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@Crssmk … you also have to realize what adjustment to make, ph or ppm. its different if the plant is drinking or not. I found in the bucket, i set my ph for the growth stage and adjusted ppm up or down to whatever it would eat. If my ppm rose, i would adjust down until the plant would drop ppm on its own after drinking and ph would hold more stable.

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As @NUG61 has said. The ph fluctuations will only get worse as the plants and root mass get bigger. Once they are flowering youll be checking and adjusting ph twice a day. If you cant get some bigger totes it will be much easier on ya

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Heres a nice chart for reference as well.
image

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COPY/PASTE the below list into your forum post.

Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so; Or post
NA (non applicable)

-What strain, Seed bank, or bag seed (photo or auto)
-Age of plant
-Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF
-Vessels: Type and capacity of container (fabric, plastic, etc)
-PH and TDS of Water, Solution, runoff (if Applicable)
-PPM/TDS or EC of nutrient solution if applicable
-Method used to measure PH and TDS
-Indoor or Outdoor if indoor, size of grow space
-Light system List brand and wattage/spectrum
-Actual wattage draw of lights
-Current Light Schedule
-Temps; Day, Night
-Humidity; Day, Night
-Ventilation system; Yes, No, Size
-AC, Humidifier, De-humidifier,
-Co2; Yes, No

If growing Hydro some additional questions:

-DWC? RDWC? Autopots? Ebb and Flow? Other?
-Distance of liquid below net pot (DWC)
-Temperature of reservoir
-TDS of nutrient solution
-Amount of air to solution

Always try to upload a clear picture in white light of any issues you may have to allow the community to assist you.

Myfriendis410
Regular
2h
COPY/PASTE the below list into your forum post.

Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so; Or post
NA (non applicable)

-What strain, Seed bank, or bag seed (photo or auto) Autoflower White Widow and Runtz Auto
-Age of plant week 2 of veg day 21 from seed
-Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF hydro DWC 5 gallon 3 inches below basket. About 1.5 gal
-Vessels: Type and capacity of container (fabric, plastic, etc)
-PH and TDS of Water, Solution, runoff (if Applicable) ph this am was 6.4 tec was 1000 i added nutrients back up to 1800 ec and ph is now 5.8
-PPM/TDS or EC of nutrient solution if applicable
-Method used to measure PH and TDS ph meter recently calibrated in 2 diff buffer and EC meter also calibrated recently
-Indoor or Outdoor if indoor, size of grow space
Indoor
-Light system List brand and wattage/spectrum

-Actual wattage draw of lights 400watts
-Current Light Schedule 24/0
-Temps; Day, Night was at 80 i lowered to 76F humidity is 65-70
-Humidity; Day, Night n/a
-Ventilation system; Yes, No, Size no sealed tent with inline fan and carbon filter 1 clip fan and 1 oscillating fan 13 inch jyst added for more airmovement
-AC, Humidifier, De-humidifier, ac and dehumidifier
-Co2; Yes, No
yes xl exhale bag now only 800 ppm of co2

If growing Hydro some additional questions:

-DWC? RDWC? Autopots? Ebb and Flow? Other?
DWC
-Distance of liquid below net pot (DWC)
3 inches
-Temperature of reservoir
Was 75 sincince i lowered temp to get my vpd to .8 it is about 65 degrees
-TDS of nutrient solution
Ec was 1000 i raised back to 1800 which lowered ph so i added a lil up from 5.1 to 5.8 after i added nutes
-Amount of air to solution 4 airstones

Always try to upload a clear picture in white light of any issues you may have to allow the community to assist you.

I aslo have the ac infinity complete sys yesterday i realized that the humidity was off by 12% so i calibrated that and i calibrated temp it was off by 2 degrees

20221004_114233

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This is the feeding schedule i use i have the whole line except the cal-mag which i know i know i should have it but i dont

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I try to keep the humidity about 70% to keep the kpa under 1.0
I didnt realize the plant looks more yellow on new growth under the light till i just now pulled out of tent to take a pic

So, a couple of things I see:

You want to be at or around 900 ppm NACL scale or 1.8 EC with a PH between 5.3 and 5.8.

This should be closer to 1.5 to 2".

This does nothing for you: I’d ditch them.

What is your liquid temp? Needs to be below 70F for oxygenation and reduce the incidence of pythium (root rot).

FYI most of the FF grow schedules use Canadian/Imperial 700 scale, plus they’re a bit ‘generous’ with the nutrient load. Stay around 900 ppm in veg (500 scale) and bump to 1,100 once in flower.

This and silica both are necessary in hydro. When mixing: silica first, cal mag second, followed by everything else.

Setting up a 20 gallon tote instead of those buckets will help with nutes and PH along with maintaining proper distance below net pot. You’d be amazed at the difference. Once in flower you will be topping up your buckets twice a day FYI.

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The water temp is 65 and i use ec as tds differs from country to country so my ec is now 1.8 or 900 ppm tds

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I jyst use the bag to keep co2 since i have a sealed sys ive heard mixed reviews on the bags i will use till it is dead dont wanna just throw them out

Also one other thing if i convert this system to a recirculating system do i still need the air stones doing this would make my life easier lol as all id have to check is the reservoir which i can build or do anything and what size recirculating pump should i get i only do 2 buckets 5 gal each 2 plants with a 3rd being the reservoir

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I used this guy for my RDWC. 27 gallon tote for the main reservoir, 3x5 gallon buckets for plants. Amazon.com

In retrospect I wish I had gotten a bigger reservoir, because about half full (so the water level is always 2-3” below the net pot), I ended up somewhere around 20 gallons or so total in my system. That’s fine but on reading, less water = harder to regulate those PPMs and pH, as you’re finding out.

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You do. DWC has to be aerated so roots acquire O. I had a four plant system and used a 450 GPH pump. The larger the rez, the better for stability.

I picked up a plastic barrel from a local car wash for free. They have 15, 35 and 50 gallon. If you do go that route, make sure you get one that had soap in it and not wax. Clean out with a garden hose and you’re in business. A float valve to a check-rez will help maintain proper liquid depth.

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What kind of system are you using?

What size piping do i need im only using 2 5 gal buckets and a larger reservoir