What do these pH and ppm readings tell you?

[fanleaf]

My 1 month old AK47 is a bushy beast. For the last few weeks I have been battling a runoff ph that started at 5.2 that caused lockout. I've been fighting to get it up to normal for a few weeks now and heres what happened the last few days.
The last time I watered the plant I had the runoff up to 6.0-6.1 and 600ppm TDS. I had been feeding at about 500ppm.

I waited until soil was dry and the plant needed fed. I fed it what I feel is a heavy feeding. And I know I was having a mag deficit to deal with too.
Heres the list of what I had in the gallon of distilled;

3tsp Grow Big
2tsp Big Bloom
1 and a half tsp CalMag
1/4tsp superthrive
1/2tsp 29% h2o2
The total of this came in at 870ppm which I ph'ed to 6.8

The reason why I added the h2o2 was because I know I over watered a few times when the plant was really young and even though I tried to let it dry out I just always had the feeling that there was still a wet spot deep in the rootball. 1 hint was even though it had been 3-4 days since a water and the soil felt dry when I would water most of the leaves would lay down for several hours and then perk back up so I figured I would add just a bit of 29% h2o2 and see if that helped.

So I then fed with the cocktail above a few days ago
The leaves never layed down like they have at every other watering! Thanks h2o2!
When I fed at 870ppm and 6.8ph I fed until I got some runoff and the runoff tested at 820ppm and 6.0. The 820 was understandable because before this I had only fed to 550ppm at most. The ph is still at the low end at 6.0.

Now today. Only 2 days later the plant looks good. Nothing looks bad and the plant was ready for water already. The plant felt really light for only 2 days since the feed. So I watered her.

Watered her with ph'ed distilled at 6.8. This time it took a whole gallon!
The runoff was 6.4 ph and only 410ppm!
Does this tell me she needs fed even more?????? I fed at 870ppm! Also FINALLY my ph for runoff is great at 6.4!
Did the h2o2 do that for me? I've been fighting the runoff ph for 2 weeks. I add a half tsp of 29% h2o2 and BAM, everything seems to have fallen in line.
What do you more experienced fellas take from this?
Shes a big girl for her age. Only 13 inches tall but as of this morning 23 inches wide and 10 tops at the canopy!

 

[Weaselcracker]

I wish I knew enough to help you out more. I'm partly just posting so I'll be subbed cause I'm curious what others say. I don't use peroxide much.
One thing does occur to me though-
As you've probably noticed, it takes more ph plus/minus to shift a high ppm solution than a low ppm solution. Adjusting the ph of a nutrient/water mix will take a lot more ph +/- than plain water will. Know what I mean? So- the opposite applies as well. If you are trying to shift the ph of soil by pouring ph-balanced solution through it- a higher ppm solution will do the job much better than a low ppm one will.
This may be the reason why you've had better luck this time around.
If your problems persist you may want to look in to top-dressing with dolomite lime. I haven't done this before so can't help you there but a little googling should turn something up. Good luck!

 

[fanleaf]

Thanks for that reply. I did top dress with dolomite a little over a week ago so maybe that's just now showing up too. I know with fox farm OF soil from now on it will be cut with perlite and dolomite before anything even gets planted.
I do know what you are saying on the ph up/down and I guess that's a thought too. Well I just hope it all stays the way it is right now lol

 

[OldMedUser]

High Fanleaf

You don't want to be adding the peroxide with your batch of nutes. It'll just react with anything organic in the nutes and won't make a difference in the root ball at all. If your plant is growing ok now just avoid overwatering and drop the peroxide. Peroxide won't affect the pH either way.

You, like most, don't check your runoff properly for pH. You need to water until saturated then discard that runoff. Let it sit for 12 hours or so then add enough plain water to force some more run off and test that. It takes time for whatever is in the rootball to stabilize and give a true reading. Go easy on the dolomite or you will lock your pH at 7 and supply more Ca and Mg than needed especially if you are using calmag, which with tap water, (if that's what you are using), that contains those minerals will end up causing problems.

You can't really relate the ppm of your runoff to what you put in at the top so don't fret.

L8r

 

[lexort420]

Im gonna go out on a limb and guess its the dolomite lime kicking in but be careful with it like oldmeduser said. I only use h2o2 to flush my soil or to make it puff up again as my soil less mix sinks after a while but i also don't grow organic nor do i add the h2o2 directly in my water supply or nutes. I just add it to my cup that i water with at a ratio of like 1 part h2o2 to like 3 or 4 parts ph'ed water. But like i said i only use it to flush or puff up my soil less mix so not very often do I need to do it. Take it easy friend

 

[Weaselcracker]

Geez- I've got a lot to learn from you, OldMed. I hope you stick around and continue to confuse me with all the stuff I don't know.

 

[OldMedUser]

I got that info from a NC University site called PourThruInfo dot com. Just checked the site and can't bring up any of the .pdf files. Could be temporary so I'll try it later. Great info on all sorts of growing topics for plants other than pot but very applicable.

L8r

 

[fanleaf]

Thanks. You are correct. If the correct way of measuring runoff is how you say then I have indeed been checking it wrong. It's been about 12 hours now so I'll go check it the way you suggest.
As far as the Dolomite goes, no I use only distilled and had a Mag def show up so I started the Calmag. When I dressed the soil with Dolomite a while back I just dusted the top and being a complete newb am sure it wasn't overdone.

Your response did leave me with another question though.
Lots of people bubble their water or water and nutes to oxidize the water for the soil right? So it seems there would have to be a point where h202 would be safe for the organics if not added to a point of a concentration to kill them right? I ask because I only added 1/2tsp to a whole gallon and I would like to know or be able to figure out how much can be added per gallon so it acts the same as bubbling the liquid with an air stone. Thanks

Update....I did as you said is the correct way of measuring runoff ph and TDS. It has been just over 12 hours since I watered with distilled only. Now the runoff reads 6.5 and TDS of 282ppm vs earlier catching the runoff while doing the main watering which read 6.4 and 410ppm. So it seems that the water I just now added to recheck the soil may have just flushed some more of the nutes out as well as the added flushing water with a ph of 6.8 bumped the runoff reading up by 0.1. So really it seems like waiting 12 hours and retesting again added no additional info from the 1st runoff i checked except now the plant is that much more soggy. Am I wrong? I've had to fight extremely low runoff ph for a while now. Now it feels like it's under control. I hope!

 

[OldMedUser]

A little peroxide won't hurt but as it reacts with any organic matter it loses it's availability to the roots before it can be much help. You have to remember that the oxygen molecule released by peroxide is just a single atom of oxygen, O⁺, and not the O₂,O=O, that us and all other living things use to live.

The single atom of oxygen has a strong need to bind to something and is highly reactive. It basically oxidizes anything it comes into contact with that is organic. That's why it will help prevent root rot that is caused by an anaerobic bacteria. Those kind grow best in an oxygen deficient environment and cause decay while using oxygen around them making conditions worse. Aerobic bacteria, the good bugs, already have enough oxygen in them so are less likely to be affected by the peroxide until all the bad bugs have been oxidized. When you get a bit of the strong peroxide on your skin the first to get oxidized are the dead skin cells on the surface then it attacks the living cells. Same in the root zone. The O⁺ atoms have a stronger attraction to oxygen lacking bad bugs than they have to the good bugs and will kill lots more of them than good bugs until all the bad ones are gone. It also oxidizes any other organic material present like coco, peat moss, dirt and roots. Dead roots first tho.

It's best to aerate the water with an airstone than count on peroxide to supply oxygen to your plant.
L8r

 

[fanleaf]

Thank you so very much for taking the time to explain the difference. Makes perfect sense and I understand now.