DWC Nutrient Strength?

Joint Monster

Well-Known Member
[Yellow Leaf Tips / High PPM / 3 Days after res change]
This may seem like a really simple answer and I am probably just over thinking things...

I did a res change (1/2 empty the res, add ro water and nutes at full strength according to the entire system size. Then add my Tea.)

PH 5.8 / PPM 2000 -> It has stayed stable here, has not really gone down or up. PPM will go up and down by like 20-30-40-50, but always comes back at 2000.

3 to 4 days later I have yellowing tips/leaves. Definitely looking N / hungry. It's nothing crazy, but they're definitely hungry...(If they are yellowing, is it safe to say the girls have used all the nutrients or at least the Nitrogen available in the nutrient solution?)

I don't want to keep putting more nutrients in there as I feel It's pretty high PPM already, and it feels like I'm throwing nutrients down the drain. (i.e.: 300ml CalMag per Res Change...) Should I top off water with 1/4Strength Nutes? Or should I do a res change early? (1/2empty and add full str. nutes). Or just ignore it until next res change?
And then next res change maybe bring it up to 2100 or 2200PPM?

(Otherwise, the only off thing is low humidity - however I mist hourly to make up for it, for now. I do have a humidifier. But that shouldn't make them eat that much more?)

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JSB99

Well-Known Member
[Yellow Leaf Tips / High PPM / 3 Days after res change]
This may seem like a really simple answer and I am probably just over thinking things...

I did a res change (1/2 empty the res, add ro water and nutes at full strength according to the entire system size. Then add my Tea.)

PH 5.8 / PPM 2000 -> It has stayed stable here, has not really gone down or up. PPM will go up and down by like 20-30-40-50, but always comes back at 2000.

3 to 4 days later I have yellowing tips/leaves. Definitely looking N / hungry. It's nothing crazy, but they're definitely hungry...(If they are yellowing, is it safe to say the girls have used all the nutrients or at least the Nitrogen available in the nutrient solution?)

I don't want to keep putting more nutrients in there as I feel It's pretty high PPM already, and it feels like I'm throwing nutrients down the drain. (i.e.: 300ml CalMag per Res Change...) Should I top off water with 1/4Strength Nutes? Or should I do a res change early? (1/2empty and add full str. nutes). Or just ignore it until next res change?
And then next res change maybe bring it up to 2100 or 2200PPM?

(Otherwise, the only off thing is low humidity - however I mist hourly to make up for it, for now. I do have a humidifier. But that shouldn't make them eat that much more?)

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Wow, 2000 ppm is really high! You might be experiencing nutrient lockout, which is going to resemble nutrient deficiency. I'm a month into flower, and my GH Maxi TDS is hovering around 800ppm, and I doubt it'll get any stronger.

I would drain, fill with tap and run for an hour, drain again, and fill with tap again. Run straight tap for a day, then drain and fill again. Start off around 600ppm and work up from there. But see how they do hovering around 800ppm.
 

rkymtnman

Well-Known Member
^^^^ agreed. that's an EC of 4 which is absolutely crazy high. i never go above 1.2 ish or 600ppm.

i'd flush with RO/distilled water for at least 12 hrs and then start back at 1000 ppm and see what happens.
 

Joint Monster

Well-Known Member
Thanks guys!

From the intensity of those replies I figured something must be wrong! I put my guardian on EC and it reads 2.8. (I am only giving about 60% of what the GH feed chart recommends for my stage of growth and system size.)

Based on rykmnt's digits, that should be around 1300ish? Do you think my meter is reading PPM off? (PPM - ecx700)

Also before I do flush, since I'm running bennies... should I just add more Tea instead of flushing? (I added tea last night as it was tea night and that seems to have stopped the progression of the yellowing.)
 

rkymtnman

Well-Known Member
Thanks guys!

From the intensity of those replies I figured something must be wrong! I put my guardian on EC and it reads 2.8. (I am only giving about 60% of what the GH feed chart recommends for my stage of growth and system size.)

Based on rykmnt's digits, that should be around 1300ish? Do you think my meter is reading PPM off? (PPM - ecx700)

Also before I do flush, since I'm running bennies... should I just add more Tea instead of flushing? (I added tea last night as it was tea night and that seems to have stopped the progression of the yellowing.)
only use EC would be my recommendation. then you never worry about conversion factors ever again.
for instance, here's a rough EC schedule that i follow (high altitude) seedlings .2 to .4, early veg .6, rest of veg and bloom 1.2, last 2 weeks .8
 
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