PPM’s and PH are messing me up

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TheGreek_978

TheGreek_978

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Hey guys so I have a question or statement that I need help with.

I’m running a DWC system and this is my 2nd time growing this way. When my PH rises so does my PPM’s and when I lower the PH my PPM’s lower too. I try to keep her from 5.5-6.2 range for PH. And for PPM I started it at 400ppm’s and she jumps around

She’s almost at a month old from seed to her state now. I feel she should be much bigger than why she is. I can see her roots and they are nice and white but not really stretching down a lot.

What do you guys think might be happening with the fluctuating numbers

or is it just me and she’s right on track. Thank you guys
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M0nStarNuggety

M0nStarNuggety

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What nutrients are you using? Mixing process? You will a have minor PH rise naturally as the plants drink and use the nutrients. But your PPM will drop slightly also.
 
Aqua Man

Aqua Man

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What's your source water? RO?

This sounds like a buffering issue in terms of PH.

With the ppm it's possible that at the lower PH they are eating more which is a good thing and kinda days that they like the lower ph.

Ppm will rise or fall when the plants take up water... generally a rise indicates the plant is taking up more water than nutrients and a fall means the plant is taking up more nutrients than water.

Ph plays a role in availability and I find 5.6-6.0 a good range phong down to 5.6 and letting it drift to 6.0-6.1 before readjusting. Ideally about 0.2 increase in ph in 24 hrs is what I like to see. This is easily controlled with a ph buffer like potassium silicate, potassium bicarbonate or calcium carbonate. If you are using RO you will likely need to add a buffer. I'll link a thread I did that gives a bit more info.

Your humidity (VPD) will have a large impact on the uptake if both. I'll link a thread that describes that but understand it's a guideline not a hard rule.

I'll link one more on top ups also just incase you may like the read. Imo once you add back the volume of water your system holds ( in your case about 3.5 gal) you do a complete res change. This is to keep nutrient ratios in check. This can range from 3 weeks to 3 days depending on the stage of growth and uptake.




 
Aqua Man

Aqua Man

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Oh 1 more thing if you are using ph perfect I would speak up cause you don't want to be ph adjusting that stuff and should be used with RO. Basically ignore the ph and only concentrate on ppm if using that line.
 
TheGreek_978

TheGreek_978

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I am using normal tap water which has a PPM of 150 on it own. And for PH I’m using PH down and PH up to adjust. I’m also using Cal mag
 
Aqua Man

Aqua Man

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I am using normal tap water which has a PPM of 150 on it own. And for PH I’m using PH down and PH up to adjust. I’m also using Cal mag
What brand of ph down?

Cal mag generally will lower ph contrary to what many say. Because it's usually cal nitrate and mag nitrate or mag sulfate. Although some do contain calcium carbonate it's rare.

How much of a ph change do you see in 24hrs?

What nutrients are you using?
 
TheGreek_978

TheGreek_978

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I’m using general hydroponics

bloom, micro and grow

and for the ph adjusters I am using general hydroponics for that

so let’s say before bed around 1030pm I get the PH down to 5.6 and before I head to work around 6:30 am it’s at 6.0 so not a crazy spike. Buts it’s the PPM’s they will go from 350 beofre 10:30pm to 420 at 6:30 am
 
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Aqua Man

Aqua Man

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I’m using general hydroponics

bloom, micro and grow

and for the ph adjusters I am using general hydroponics for that

so let’s say before bed around 1030pm I get the PH down to 5.6 and before I head to work around 6:30 am it’s at 6.0 so not a crazy spike. Buts it’s the PPM’s they will go from 350 beofre 10:30pm to 420 at 6:30 am
That's ok just top up with water.

Yeah you need to add a buffer. You ph up should be potassium bicarbonate. So if you start off by adding 50ppm of that then mix your nutrients as you are and ph down last.

Give that a try for now. Potassium silicate would be a good option as plants love silica.
 
Aqua Man

Aqua Man

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awesome thank you! I just did it now and I’ll continue until I see the roots hit
Once they hit the water you can expect much more explosive growth if conditions are even just decent. They will grow that much or more in a week if that.
 
TheGreek_978

TheGreek_978

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Ya I’m surprised, cuz on my first grow I felt it took off super quick. Never top fed either
Once they hit the water you can expect much more explosive growth if conditions are even just decent. They will grow that much or more in a week if that.
 
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