Runoff PPM's in coco

Hello all, question about runoff ppm’s. If I’m feeding around 1500 ppm’s in 4th week of flower, what range should my runoff ppms be generally?

1500 is high. I like to stay below 1400.

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@latewood posted something saying a little lower ppm in flower will give the same results but with better tasting weed.

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Well, I have a low ph issue, runoff is between 5.2-5.4. So I’ve flushed with 5.8 R/O water, reduced my ppms down to around 1000, and ph’d that at 6.2 to try and bring it up. The thing is, they look really good. We shall see.

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Stay with the lower number unless the plant tells you differently. For example: input TDS is (say) 1,200 ppm. Water to runoff. Nest day do a straight R/O and capture first 10% of runoff and measure. If the runoff is higher than 1,200, like 1,500 ppm, then the plant is not uptaking what you are putting in and is just wasted. If however the runoff starts off low or at 1,200 ppm you can take your nutrient load up a bit. But you have another dimension to coco in that normal interval feedings of F/W/F/W can be changed to something like F/F/F/W. This will introduce a higher average overall nutrient load to your plant.

PH 5.9 to 6.0 is what I target in coco and Promix both FYI. Hopefully you are using cal mag. I would only discontinue when the plant starts to take in less nutes.

FYI using low TDS water to adjust PH is a waste of time. There is nothing there (no solids) to drive the media PH up or down. At feedings, yes, but don’t exceed 6.5 or so. Pot size can have an adverse affect on media PH.

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@Myfriendis410 thanks for that, the plants look really good. The Canna A & B supposedly have everything I need without supplementing cal mag, and thus far I havent seen evidence that they are deficient in it. The low ph has me a little concerned, because according to what I have read phosphorus in coco isnt able to be utilized under 5.7 or so (not sure how accurate that is). Yesterdays feeding got ph’d higher, which I will continue to do based on your advice, until my numbers are up. Also, I’ve been feeding daily; any reason to change that?

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Yeah; best to run coco with frequent water only intervals. Salts build up and you can develop issues with it. What is likely happening if you are in a smaller pot (3 gallon?) the root mass occupies the entire volume and struggles to support the canopy. Salts are exchanged and drives the PH down along with organic material dying off.

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That makes sense, I’m in 5 gal pots and they got much bigger than I had planned.

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I’ve over driven a plant and essentially had it just give up trying to make flowers: that plant turned into edibles.

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Yeah I’m hoping to not have that happen

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I’m pretty sure I screwed this up, but I hope I can bring it around. Not enough water feeds and heavy feeds have my runoff ppms embarrassingly high. Given the size of the plants, 5 gal pots, I’m thinking I have dead root material buildup, salt build up, nute buildup, and whatever else could be built up. I’m headed to the store for some Florakleen, Cannazym, and maybe some Canna Boost. They look really good, but with runoff PPMs over 2000 on all but 1, and ph between 5.2 and 5.4, I’m having a freak out moment here.

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First; relax. Your plants don’t look too bad.

Second; Florakleen and a reset with beneficial microbes is a good thing. You can buffer the coco with a top dressing of dolomite lime too which should bring things up a bit too. Your yields MAY suffer on this grow but you will be ahead on the next one.

Stuff happens.

I like your attitude: we see some who blame everything but something they may or may not have done. This is different from anything else you’ve done, likely.

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It is, different lights, different food, different strains…I really appreciate the feedback @Myfriendis410. I’m gonna have everything mixed and ready to go when the lights come on.im 4 weeks since the flip, so maybe 3 weeks into flower. I’m hoping they respond well.

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You get the best tasting pot using a ppm of 1000-1200 ppm

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I would never flush just because my runoff ph was a little low. Just raise the solution a point or .2

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I also grow in coco and keep the ph 5.8-6.2. I feed every watering also. Maybe not needed but my last grow was really good using this method. As stated above, use cal mag. Coco absorbs it very readily until it is saturated.

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@latewood thank you for the feedback. My ph is one issue, the other is my lack of water feeds and heavy daily feedings have built up (I believe) based on extremely high runoff ppms. The plants look good, not much of any tip burn etc, but I’m thinking they need some of that removed. My bad for not monitoring g my runoff more closely, but when they appear to be thriving, I figured all is well. @Familyman would you recommend supplementing some cal mag, even though the Canna A & B is for coco and should have it in there? If it cant hurt, I have cal mag here so I’m all for throwing some at them if it will be beneficial. Thanks all!

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I would

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Ok, I feel better. After the Floraleen yesterday, I fed a half feeding and included a full dose of Cannazym, 636ppms. All runoff ppms are in the 1300 ppm range, and ph is 5.7 on all except the Chocolope, which is 2000 ppms and 5.3 ph. I’ll see what it looks like tomorrow. They do look happier, it’s amazing how quickly they can recover (or take a nose dive).

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Once you find the sweet spot they’ll take off

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