Measuring the run off ppm... Coco

This is probably stupid but here it goes......
I've had this auto flower OG kush in coco 1gal fabric. Growing fine I suppose. Other day I read an article on "coco for cannabis" about managing your coco feeding by measuring IN and OUT ppm. The out run off should be round + 300 from your in. If I'm understanding correctly.
Figured I'd measure mine and see.....

Using GH flora series I'm only getting a 750ppm (300 of that is my damn tap water) that's my feed IN. My OUT was1100.
So not horrible right?
Thought I'd get it closer in range by increasing fertigation.. measured again after 2 feeds closer together.
750 IN. 2000 OUT!!!
Should I be concerned about this?.. go back to my usual 1 feed? Or Someone just tell me to quit thinking and just keep doing lol
I have a very slight nute burn it appears. But with only 750ppm feed. I thought maybe the burn is coming from the run off swing?

Are you feeding to plenty of run off? The purpose of run off is to wash out any extra salts that build up. Also, how many times per day are you feeding? 750 shouldn't burn the plants BUT if you let them get too dry between feedings, the EC of the media will skyrocket and you can certainly burn your plants. You really don't need to measure the run off ppms unless you see something seriously wrong-runoff is notoriously inaccurate...but if you are troubleshooting a major problem, then measuring runoff (collected in a clean container) can tell you a few things. 1 gallon pots dry out almost instantly with coco, so I think that's why you got the burn. Unless you are going to feed 5 times per day with an automated system, a bigger pot is much easier to deal with.

I don’t do coco but my instinct tells me to flush with a lower ec solution until my numbers are closer. Resume feed at a bit lower dose. Someone else will chime in.

Will add that runoff was prob lacking to get loaded up.

I'm new at growing so I track my coco runoff when I water. I'll say what I look for.
Feed
500ml, 400ppm 5.8ph
waste
90ml,
212ppm 6.1ph
Right now I'm really trying not to burn it again

When the waste ppm gets over what I'm feeding ( that 300 sounds like a good number ), I either feed a few times with more ml. say 1000ml instead of 500ml of 400ppm 5.8ph, to try to flush without actually flushing.
If that didn't work I would actually flush it with just ph'ed water, until the runoff tested the same as what you are putting in.

Maybe somebody can chime in, but there a times when plants will dump nutes I think, maybe when you lockout or ph is off, the ec seems to get high fast.

Wonderful info! And quick.
@Rurumo I have only been feeding once at lights on. I'd say 10% run off. So ya. Coco is gets pretty damn dry. (Duh me)
Yesterday was the first time I fed twice. Once at lights on and again 12 hrs later. (18/6 light schedule) that's when the run off swing was so big tho.
It was still very moist today at lights on but I fed again anyways. So I'll continue that to keep the coco from drying out. Thanks

@Roy O'Bannon Sweet. Love to see your actual numbers. Thanks

I’m just starting my first coir grow but from what I’ve been reading watering the plant more often should lower your Ppm if anything.

A lot of articles deal with feeding up to 5 times a day so as long as your mixture is correct there’s no downside to increased watering.


Like he said drying out is what causes issues. All the water gets removed leaving dried up nutrient salt deposits. At that point watering more with the normal mixture would flush the extra out and balance everything.