Ph fluctuations

Lkmaryfla

Member
Hello had issues with plants when I left town, came back to a tent with full blown lockout. Ph on run off was 3.6-4.3 on 6 plants and ppm was around 1200-1500. All plants show stress and deficiencies. So I flushed 40 gallons through each 3 gallon pot, ph was 6.3 and ppm was 300. Got the ppm down to 400-600, and ph up to 5.1-5.4. It's been a week of this and see no positive change. It's actually gotten worse. I was told to do a slurry test and ph came back high while runoff showed low? What do I trust? Slurry or runoff... slurry contents came from 3 inches in coco and ro
 

Punk

Well-Known Member
Hey there,
I will say that 40 gallons is a bit excessive for a flush. a couple gallons of warm water, followed by an hour pause to 'loosen' it all up, and then a couple more gallons to actually flush it out, it's a lot easier on the plant and is more effective at rinsing the soil. I do that about midway through flowering.
Other than that, just test and adjust you water before you give it to your plant, like right before you pour, make sure you test it. Even after you adjust a bucket of water, it will drift back to its original ph in about 24-48 hours.
 

Hook Daddy

Well-Known Member
What is your medium? You mention coco but nothing else. If in coco quit trying to flush. If you actually want help post pics, medium, lighting, ph, ppm or ec, etc and then someone might have an idea what’s going on, otherwise everyone is just guessing.
 

Rurumo

Well-Known Member
Do you have any pics? What nutrients are you using? If you are using 100% coco, you should feed them at least daily, and don't feed a very low EC to try to leach nutrients out of the media. Just start feeding 1-1.2 EC to 20% runoff at least once per day, but if the roots have filled out their pots, then feed at least twice per day-this will help stabilize them. Sometimes people make the mistake of going from one extreme to another and their plants just get worse. We really need pics to be more helpful.
 

Lkmaryfla

Member
I'm in a 4x4 tent, 650 watt 6 bar light, 4 oscillating vivosun fans, Terra bloom 6"exhaust, 70/30 coco perlite, advanced nutrients cocos synsei.

The 40 gallons was over 2 days. I tried with a couple gallons at 6.1ph, 300 ppm of a/b and a few hours later with a few more. Numbers didn't budge. I didn't just pour 40 through, I checked runoff numbers every few gallons.
 

Lkmaryfla

Member
I always feed twice daily, before this mess I was feeding a/b , big bud, nirvana at 900-1200ppm and they were loving it. I think the person I had watch them didn't feed them but once or twice over a 16 day period. Before I left the runoff ph was 5.9 and ppm was 950ish, my truncheon was flashing between 1000-900. You think I should just go back to feeding 1200ppm? My runoff ppm is staying the same as what I feed it, that's why I haven't been moving ppm up.
 

calvin.m16

Well-Known Member
Dude your plants are starving that's why the runoff pH is so high. Increase your base nutrients by 20% and try using a pH of 6.0 in flower even in coco.

My plants look golden when I'm feeding 2.0 EC once daily @ 6.0 pH in 70/30% Coco/Perlite by Mother Earth brand using CYCO basic chart.

Reading runoff in Coco has not been reliable for me at all especially for feeding reference. If you flush 1 PPM water through coco with zero nutrients it will come out 1.6 EC some brands.. You can't judge your nutrient capacity due to runoff + nutrient is not going to be understandable with a $200 meter.
 

calvin.m16

Well-Known Member
Also in such dinky pots you need to flush at least once a week, by "FLUSH" I mean give pure water until a little runs off, not 10 gallons of water.
 

Lkmaryfla

Member
Dude your plants are starving that's why the runoff pH is so high. Increase your base nutrients by 20% and try using a pH of 6.0 in flower even in coco.

My plants look golden when I'm feeding 2.0 EC once daily @ 6.0 pH in 70/30% Coco/Perlite by Mother Earth brand using CYCO basic chart.

Reading runoff in Coco has not been reliable for me at all especially for feeding reference. If you flush 1 PPM water through coco with zero nutrients it will come out 1.6 EC some brands.. You can't judge your nutrient capacity due to runoff + nutrient is not going to be understandable with a $200 meter.
5.3ph runoff is high? I'm feeding 500ppm at 6.1ph the last 2 days, the ph is going from 6.1 to 5.3 and the ppm is staying the same or 550. You think feeding more at 6.0ph would help?
 

calvin.m16

Well-Known Member
5.3ph runoff is high? I'm feeding 500ppm at 6.1ph the last 2 days, the ph is going from 6.1 to 5.3 and the ppm is staying the same or 550. You think feeding more at 6.0ph would help?
My apologies I meant to say pH is so low.
4 plants are in 3 gallon smart pots and 2 in 5 gallon smart pots and the 5s are worse. You don't flush coco with water ever.
I give my plants plain water at least once every two weeks. So long as your rootzone EC is high you can do it no problem and you actually should to avoid burn and or pH issues. If you feed only a couple plants and can micro manage each plant and find the perfect EC input then yeah it wouldn't be necessary but it is not going to hurt your plants dude.

I'm going to start replacing "flush" with "give plain water" because my idea of flushing is such, not pouring 20x container volume of water.

Read your rootzone EC values with a tool such as the BlueLab Pulse monitor and you will learn when you need to give plain water. EC can get really high as certain compounds build up in the coco over time. It's good to occasionally dissolve those into plain water and allow the plant to get back to a balanced diet.
 

Lkmaryfla

Member
My apologies I meant to say pH is so low.


I give my plants plain water at least once every two weeks. So long as your rootzone EC is high you can do it no problem and you actually should to avoid burn and or pH issues. If you feed only a couple plants and can micro manage each plant and find the perfect EC input then yeah it wouldn't be necessary but it is not going to hurt your plants dude.

I'm going to start replacing "flush" with "give plain water" because my idea of flushing is such, not pouring 20x container volume of water.

Read your rootzone EC values with a tool such as the BlueLab Pulse monitor and you will learn when you need to give plain water. EC can get really high as certain compounds build up in the coco over time. It's good to occasionally dissolve those into plain water and allow the plant to get back to a balanced diet.
I fed them at lights on just now plain ph6.0 water, I'm gonna agian in 8 hours. The runoff ph was 5.4 and 450ppm. I did notice they barely drank anything from last night.
Should I feed low ppm tomorrow and ramp up or give them 900-1200 ppm? When they were healthy before I felt I was feeding 1200 at 6.1, and the runoff was coming out 1000-1150 and ph was 5.9-6.1. Thanks for the help by the way, I appreciate any knowledge
 

calvin.m16

Well-Known Member
I fed them at lights on just now plain ph6.0 water, I'm gonna agian in 8 hours. The runoff ph was 5.4 and 450ppm. I did notice they barely drank anything from last night.
Should I feed low ppm tomorrow and ramp up or give them 900-1200 ppm? When they were healthy before I felt I was feeding 1200 at 6.1, and the runoff was coming out 1000-1150 and ph was 5.9-6.1. Thanks for the help by the way, I appreciate any knowledge
More base nutrients for sure.
 

PadawanWarrior

Well-Known Member
This is a great thread about pH and pH correction.

 
Top