Safely bringing up nutrient levels in soil grow

Indoor soil, Growing in Foxfarms ocean forest.

Grand daddy purple bought through

LED lights Running about 40k lux at canopy top @18/6 light cycle

pH stable at 6.7ish

Temp around 75 degrees or so. Relative humidity around 45%

4x4 tent, ventilated.

Nutrients are fox farm trio.

My PPM 500 reading has been around 450ish on the runoff for the past couple weeks. After feeding it seems to not have changed. My gut tells me I need to add nutes until it is in the proper range, but my brain is telling me that will burn it. Any advice for safely bringing the nutrient levels up in soil?

Progressively raise your feeding PPM until you reach a runoff PPM of ~1,000 and then maintain it there.




So, if I water it every other day can I go ahead and feed each time as well till it gets to the 1k range? or should I feed every other WATERING? been following the guidance that less is more especially with my lack of experience

as I’m still new to this… should I water with nutrient solution that measures about 1k before watering, or follow the directions on the nutes?

I’m just now beginning to get a watering routine. as such I’m putting about a gallon of water pH’d to 6.7 and was beginning to add nutrients every other watering. I would add smaller amounts of water in between if it seems dry.

Got this lady in a 5-gallon pot
She is about 9 weeks old. about 5 weeks in this soil after transplanting

Unfortunately there is not one definitive answer or path to take. You have to take in as much information as you can and then choose what you think will work best for you.
I don’t ever do plain waterings, I use nutrients every time. I’m not saying that people who do straight waterings are wrong, it might work great for them, but through a tremendous amount of trial and error, I’ve found that the more consistent I keep the feedings the better my plants do. Because I feed at every watering, I keep the EC/PPM of my solution a little lower than if I were feeding every other time.
As far as your current situation, I’d suggest raising your levels, but definitely slowly. I wouldn’t raise the level of your solution more than 100 to 150 ppm at a time. In other words, if you fed them at 450 ppm last time, don’t go any higher than around 600 the next time, and so on.

Wow runoff ppm of only 450 using FF OF! I have a hard time getting runoff that low using coco.
What is feed ppm?
If runoff has consistently been 450 it means the plant is consuming everything you feed it plus the soil is basically depleted.


Thanks guys! great info!

What pens do u have for reading tds? Have you calibrated? Seems low for ppm especially in FF.

I am still learning this. At first, I was adding a bit less than the directions said to (like 3 to4 tablespoons per gallon etc.). last feeding I raised the PPM to 1100 but that took a bit more than the recommended amount. Sucess in anything entails creating good habits and consistency. but that comes with experience. I’m not yet there LoL!

I have the Bluelab TRUNV2 Truncheon Nutrient Meter. as far as I can tell there isn’t a way to calibrate. : Bluelab TRUNV2 Truncheon Nutrient Meter, Digital Conductivity Tester in Water (Scales Include: EC, 500, ppm 700, CF, TDS) Tool for Hydroponic System and Indoor Plant Grow, White : Plant Germination Equipment : Patio, Lawn & Garden

I started with the trio but that was a couple years ago

PPM of 1100 (500 scale) is pretty lite for FF Trio. But, their feed schedule is heavy handed.

Do you have any pictures? I just finished a grow of GDP.
How old?

It’s about 9 weeks in right now. but it has been in a growth slump lately. standing at about 22" from top of pot. feel like it should be about 1/3 bigger.
Chasing problems associated with my ignorance lol. but it seems its almost back on track. I’ll let it recover from this before switching to flower.
I’ll post a pic or 2 when I have time

They say in here ‘without pics it didn’t happen’ lol

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This is one of the GDP. I flipped her on day 63

Pruned to 8 colas manifold with a little scrog to help spread her out

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I’ll try to get a couple pics this weekend! my work schedule is crazy. only giving me a few minutes a day to tend to her. So, no time for the SI photo shoot lol:)
But yours look great! Maybe I’m not too far off target. If yours are 22"ish I’m right there too. I haven’t topped mine, but it is branching out like crazy!
I may give it another week or so before I flip it.
it was sprouting october 1

heavy Indica will do that. It needs to be thinned out.
The underside when she was flipped

She was bent and tied several times before flipping

This may sound like a stupid question but Are you adjusting the ph of your water before or after you add nutes?

Not a stupid question at all. Am still working on routine, but yes-ish. have pH’d it before adding nutes then checking afterwards. but lately I’ve been adding nute then pHing. my tap water is 8.5ish so I put it in a gallon jug and let it sit open for a couple days to let chlorine dissipate.
Since I have no baseline of comparison, I’ve been all over the map! its taking me this long to even figure out how to water sort of correctly lol.

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Hey Beardless,
Since you’ve grown and are growing this strain,GDP, I have a couple questions if I can. Given that it branches out quite nicely on its own is there a significant advantage to topping this plant? if so, would it be a bad thing to do it now? Our plants are about the same age and height. have not switched light cycle yet. Trying to get a leaf issue under control first. and of course, get nutes in the right quantity. also, on an indoor grow such as mine, what realistic expectation could one have as to possible yield for 1 plant? the web site says around a pound, but it’s not clear whether that is indoor or outdoor or both.

Thanks again to everyone for the input!