Brand new coco-Why is the first run off at 4.2 ph?

First post,

I've dabbled with a lot of mediums and decided to try coco. I picked Cali Substrate coco. I took some nice rooted clones, new pot's, new nutrients ETC.

For nutrients I'm trying Elite nutrients,A,B,C and their root igniter for veg. 3 mil's of A and B per gallon and 2 mil's of root tonic (C) per gallon and 2 mil's of root igniter per gallon to target 400 PPM for week 1. I also adding 3 mil's per gallon of H202.

I transplanted the girls and feed @ 6.1 PH only to read the run off between 4.4-4.2 PH. I've never heard nor seen such a thing, so I'm looking for some solid advice. Is this normal for coco? Should I ignore PH run off as the PPM's are the same? Is this coco a bad batch or garbage? The only thing I can think is the extra Cal/Mag they add too the coco that might be the cause of such a low run off.
This is new to me, but I've never had an issue with any medium on the first watering

I would flush it out with 1/4 strength nutes including cal mag at 6-6.5 ph till desired runoff is met at about 5.5-6ph and your ppm of run off stabilizes at a normal range

Continue flushing with your nutrient solution pH'd between 5.8-6.2.

I use Canna and even they put out a rough batch. When I transplant, I flush with nutrient twice.

Coco has very little CEC re: the ability to hold nutrients. The solution in the medium is your medium EC/pH. If you want to correct, continue applying the ideal solution, not a correction or weaker dose.

You can create a slurry with equal parts distilled water and fresh unused medium. Stir a few times over 30 minutes, strain and test.

Mikell said:

Continue flushing with your nutrient solution pH'd between 5.8-6.2.

I use Canna and even they put out a rough batch. When I transplant, I flush with nutrient twice.

Coco has very little CEC re: the ability to hold nutrients. The solution in the medium is your medium EC/pH. If you want to correct, continue applying the ideal solution, not a correction or weaker dose.

You can create a slurry with equal parts distilled water and fresh unused medium. Stir a few times over 30 minutes, strain and test.

Click to expand...

Thanks for the replies.

I spoke with the owner of the company for over an hour. I used tap water and RO water with both run off's @ 5.5-5.8 but when I did a simple run off test with ph'd water @ 6.1 it dropped into the 4's.

It seems starting @ 6.9 ph with tap water drops it a full point and buy adding ph down with the water it drops it another point into the 4's. The Acid should be more than stable after 24 hours, air stones etc., so I'm kind of clueless, as is the owner atm. If I run 400 ppm @ 6.1 ph for example it drops it even lower compared to to just water and ph down alone.

It's a double washed product, Cal/Mag added already so I'm honestly lost as to why non ph'd tap water @ 6.9 OR RO water @ 6.0 runs off above 5.5 ph. He did have me to a coir ph test with 1 cup coco and two cups water. The results where the same, unless I used Ph'd water.

Any thoughts or suggestions to fix this issue?

I highly doubly it's normal to go in @ 6.1 and run off is in the 4's, so any advice I'm overlooking would be greatly appreciated.

^^Lot's of typo's.

In general, as long as I don't use ph down in my water, the coco run off is above 5.5 ph. I've don't a few different test's, but everytime I use ph water I'm in the 4's and if I make a batch of food @ 400 ppm with ph down it drops a few points lower into the 4's.

I've tried many mediums and methods over the years, so this just doesn't add up. I tried new coco in a solo cup and flushed with ph water, but it hardly brought the run off up. I also did the same with my food mix.

I can't say this is normal or it will correct itself along the way, as I've never used coco before. It was mentioned to add 1 gram per liter of lime to stable the PH, but I'm not a fan of lime and the coco seems to be good with regular non ph'd water.

Has anyone come across this issue or know what the issue might be that I'm catching?

I am in the same boat. I am using Plagron coco and BioNova Coco A+B fertilizers. I used RO water and RO mixed with tap (100 ppm) and my runoff PH is 5.4-5.6. My inlet PH was always 5.8-6.0. I am using phosporic acid as PH-. And if i non PH the inlet solution my runoff will be 5.7-5.9.

I have been using coco bricks for years now. IMO Botanicare cocogro is the best. And GH is the Chevrolet of coco. Most has fungus gnats IMO.

Even with Botanicare coco, I do a complete flush. If I don't, the runoff is like .6-.8 EC.

The flush is a PITA until you set yourself up to do it easily.

To expand a 5kg coco brick, I do:

- use a medium size plastic tote from home depot. 35 gallon size maybe. Drill a 2" hole in the bottom of the tote. And, have a 2" rubber stopper, also Home Depot. Place some window screen in the bottom of the tote.

- place the coco brick in the tote on top of the screen. Have the stopper in the 2" hole.

-Pour about 5 gallons of 125 degree water in the tote to expand the coco and kill any fungus gnat eggs. ( hot water right from the water heater. ) using this temperature water expands the brick in a couple minutes. Cool to watch.

-take out the stopper to drain hot water.

- use a garden hose to run tens of gallons of water through the coco until the EC of the water draining out is the same as the water from the hose. Then, use your hands to press down on the coco to squeeze extra water out.

- put the stopper back in.

-prepare 5 gallons of nutrient solution, with 5ml/gallon cal-mag added. Cause flushed coco tends to hold on to calcium you need extra for the first nutrient charge. Pour this over the coco and let that soak for a few hours.

- remove the stopper and let drain. But, don't squeeze out excess water this time.

You are left with pristine, charged coco. Like 25 gallons of it.

This sounds like a PITA. But, once you have the setup, it goes really quick.