Coco runoff pH out of range

[Decisive]

I have plants in a DTW 80/20 coco/perlite mix. I run the rezipe 6/9 mix with 3 ml/gal cal-mag added. I water twice with nutrients typically and flush after every second nutrient watering. pH of nutrient solutions is always between 5.8 and 6.0 and the flush water is also pH'ed to this range. Yesterday I was testing runoff pH's and I was getting readings between 5.0 and 5.3. I know coco runoff is never reliable to test but even taking a sample of the soil, placing it in RO water and testing the pH I still get the same 5.0-5.3 readings.

Why am I getting such low pH runoff when ive been consistantly watering between 5.8 and 6. I am starting to see mag lockout and maybe some potassium lockout as well. In an effort to fix runoff pH, I mixed 100 gallons of half strength nutes, pH'ed to 6 and ran it through the pots. Weirdly enough the runoff pH after the 100 gallons ran through was still between 5.0 and 5.3. I'm extremely puzzled and frustrated and I need advice on how to get my pH within range. Would it be safe to water with nutrients around pH 7 in an effort to raise coco pH to around 6?

Any advice would be appreciated, thanks in advance

 

[Hydropimp]

Do you use tap or ro?

i have the same issue did you ever let the coco get to dry?

got pics?

 

[MIway]

Guessing ya didn't preflush/treat the coir... need to exchange out the unusable salts (Na, K & the other gunk) from the coir & buffer it with usuable ones... ones found in our nute solutions. Until that exchange has happened & a buffer is reached within the coir, you will likely see higher than standard ppm in your run-off... and radically low pH.

d2w as you are, might just get away with it w/o any more thought... many don't flush/treat. Over the first several weeks, the normal feedings will balance itself out... esp if you are running with a sufficient amount of run-off at each feed.

Also, you can mix in finely ground dolomite lime into your next solution... and let the pH stay high that mix... likely be 6.8~7.0. Feed to run-off of 50% or so. Check the run-off next feed & if still uncomfortably low, repeat until raises. This route would be quicker, perhaps.

 

[DHF]

Well....you`ve sure done your due diligence on checkin shit , but if I hadta make an educated guess on why ph`s droppin instead of gradually rising once thing`s are dialed , it`d be the flush every 3rd feed that`s throwin yer medium off.......but....

It`s just a guess....There is no truer test for internal ph medium rootzone readings than what you`ve already done at the core of the rootmass , so try some H&G dripclean at 1 ml per gal with no flush and stabilized ph and ppm readings from there on out , per many many reports from old friends that`ve put it in their juice regimens........

Coco holds onto cal/mag and potassium till a certain level is met before releasing it back to the plants , so maybe up yer cal/mag and getchas some Botanicare Silicablast for stem wall strength and potassium supplement @ 2-5 ml per gal strain dependent....

As plants eat , ppm`s drop and ph rises gradually....on it`s own....Lotta folks feed too much with coco and are constantly washin juice through the rootzones before the plants can properly uptake and react accordingly....

Sorry bout yer problems Bro.......it`s usually cal/mag related with coco , so as yas said 1/2 strength flushes usually readjust ph and ppm settings , but getchas some dripclean for it`s ionic bond qualities that prevent residual salt buildups and ph problems while eliminating the extra runoff involved with DTW setups...

Peace.....DHF.........

 

[Decisive]

Well....you`ve sure done your due diligence on checkin shit , but if I hadta make an educated guess on why ph`s droppin instead of gradually rising once thing`s are dialed , it`d be the flush every 3rd feed that`s throwin yer medium off.......but....

It`s just a guess....There is no truer test for internal ph medium rootzone readings than what you`ve already done at the core of the rootmass , so try some H&G dripclean at 1 ml per gal with no flush and stabilized ph and ppm readings from there on out , per many many reports from old friends that`ve put it in their juice regimens........

Coco holds onto cal/mag and potassium till a certain level is met before releasing it back to the plants , so maybe up yer cal/mag and getchas some Botanicare Silicablast for stem wall strength and potassium supplement @ 2-5 ml per gal strain dependent....

As plants eat , ppm`s drop and ph rises gradually....on it`s own....Lotta folks feed too much with coco and are constantly washin juice through the rootzones before the plants can properly uptake and react accordingly....

Sorry bout yer problems Bro.......it`s usually cal/mag related with coco , so as yas said 1/2 strength flushes usually readjust ph and ppm settings , but getchas some dripclean for it`s ionic bond qualities that prevent residual salt buildups and ph problems while eliminating the extra runoff involved with DTW setups...

Peace.....DHF.........

Thanks for your thorough reply, I am sorry for not providing a complete list of nutes I use but I am using 0.5ml/gal drip clean, and I am also using dyna-grow silica at a rate of 2.5ml/ gal (half strength), they were used in that 100 gallon flush. I also am using RO water, tested to 15ppm (just replaced membrane, carbon and sediment within 1000 gals). I am also using canna coco but I admittedly did not test ppm/ph when I first potted into it. But since the runoff from each plant is relatively consistent in ppm (around 300-500) I am guessing it wasnt too high to start of with. I think I am going to flush at pH 7 and see if that raises the pH nicely. I'd appreciate any other suggestions, thank you.

 

[Buddler]

Hi ,so if your using drip clean and the rez ipe and plants are happy, why flush just keep track of whats going in eventually it'll come around flushing repeatly is just gonna mess with your buffer and retard growth, IMHO ...B

 

[Hydropimp]

DHF

I thought the drip clean could not be use in the middle of a grow because it will release all the salts?

@ Decisive do you have any dead roots in your pot?

I have flush my medium with p.h of 6.7 and still it drops down till the low 5's or high 4's

 

[Decisive]

Some of the plants are doing good, but others are showing stunted growth and Mg+ lockout. I am using smartpots and what I did after last grow was throw all pots in a 30 gal tub and I added drip clean to flush out the salts. Now rethinking it after what hydropimp said i'm an idiot, when you use smartpots roots are pruned when they break out of the pot. Last grow I had pots full of roots and tons of roots had broken out of the bottom of the pot. After soaking the pots I simply added new coco to them and potted in like nothing was wrong. About a week ago I started using pondzyme to try and break down the roots and it works remarkably well, but that coincides with the time that my stunted growth/lockout problems happened and prompted me to test pH's. I bet the breakdown of those roots is causing the pH to drop as hydropimp suggests.

Should I use pondzyme and finish breaking them all down or should I hold of and stop using leaving the dead roots in the pots. Thanks for the insight guys, so much easier to bounce ideas of other growers.

 

[DHF]

Never heard that Hydropimp.....But didn`t know pondzyme was bein used with the feed juice.....or did I misunderstand the last post .....How`s the pond zyme being used on the sp`s the plants are growin in....and.... of course decaying matter will drop ph levels and lock out cal/mag uptake......so...

Since you`re already usin dripclean , I`d up the doseage ta 1 ml per gal , since damn near everyone I`ve talked to with success stories in coco hadta up it for whatever reason dealing with the dialage of their setups...and...

Some plants are cal/mag whores and need more than other strains/varieties , so maybe you could mix up a cal/mag foliar spray for those exhibiting symptoms to keep from mixing different nutrient concentrations for the feed process....but....

Bottom line.....no pondzyme during grow cycle......gotta be the cause of your problems....good call Hydropimpster....

Good luck Bro....DHF........

 

[Hydropimp]

So check this out I started in hempy and shit went wrong my fault I had let the pots get to dry.

Then landlord came to fix the a/c in the apt.

And so on. I have a couple plants that no matter what I feed in out is low ph. I always ph 5.8-6.0.

Canna website says to ph 6.2 in veg and drop in flower. I also had fungus gnats and I don't know if I had root aphids.

So i hit them with a bayer complete insecticide product and killed them.

So what i have come to conclusion is that dead roots = low ph. I have read it in the hydro forum I think and coco is a hydro medium.

My 2 cents.

Also what is your e.c going in and coming out?

When things are not going good flush it out. Flush with a 300-350ppm and then give ½ strength nutes.

Canna makes cannazyme and they say use it in small does's through out the grow. Maybe you should do the same thing with what you have on hand.

As for my grow things are starting to get better I have the cannazym but have not used it as far as this grow. I am using boti cocogro and FNovaB

I am flowering right now and I am at 25 day I think. Post pics of the girls if you can?

Take care and keep at it.

Also if your room is to hot and plants are drinking more water and taking less nutes. You get more salt in the medium. But you use drip clean.

 

[Decisive]

Thanks for the insights boys, great call hydropimp, and DHF you didnt misunderstand I just neglected to mention it my mistake. Just shows how every single thing plays a role in how your grow is going to go. I just flushed 50 gallons (in 27x 5 gal pots) again at 1/2 strength nutes and 1ml/gal drip clean, 2.5ml gal silica, but this time I doubled my amount of enzyme. EC going in was around 1 @ .5 scale and coming out was +- 75-100 ppm on that, but mostly plus (presumably the organics from the dead roots are also enriching the media with more nutrients).

I have a feeling that if I keep going as i'm going these dead roots are going to continue to break down throughout the cycle and cause me problems down the line. With that thinking I doubled the enzyme amount and will check to see if there is a visible reduction of dead roots on the bottom of the pots in 24 hrs. In 24 hours i'll flush half strength nutes without enzyme presuming that the pH drops further as more of these dead roots are broken down.

Hopefully the plants dont suffer too much, but after watering I did a spray down with cal-mag foliar on all plants as even some of the healthy ones are showing a little deficiency on new leaves and i'll continue to foliar till my rootzone is fixed. I also have some H&G Magic Green on hand that I can use while working on the rootzone. Hopefully I can just let the enzyme get rid of these dead roots. Pondzyme is an alternative to hygrozyme and cannazyme in that while it contains enzymes it also contains bacterial cultures that produce more enzymes that break down organics as they colonize the media (maybe them growing in the media also has something to do with it). But if things are starting to look worse tomorrow I am just going to discontinue using it and hope for the best with just drip clean in the mix.

I'll post pictures in 5-6 hours when the lights turn on, thanks guys for the analysis much much appreciated.

 

[Decisive]

Heres a few pics:

 

[HawaiinRock]

i can tell you exactly what it is. stop using cal mag. seriously. unless it's GH cal mag. but botanicare cal mag has alot of nitrogen in it...and it's throwing everything off. flush very well. very well. stay with the 6/9 for now-6/10 for now...at about 700-800 ppm. everything you need is there. just ph it to 6.0 and flush with that until it comes out what you're putting in. cal mag is great at first for a charge, but if you put something like 10ml per gallon and use micro on top of that, which has a ton of nitrogen, it's over. trust me, it JUST happened to me. ran a side by side experiment with it. the ones with cal mag literally almost died. the ph of the run off was in the low 5's. the ph of the 6/9 is good. everything else green and perky. also, raise your temps a little and humidity, try to let them drink moisture from the air while the roots are healing. look at some of the roots...are they still nice and helathy, or have started to look a little brown?

i have been running a few experiments and seems like 6/9 and 2 ml grow and the plants are even a little greener. will know more in the next day or two...keeping a ver close eye on them...

 

[Buddler]

I grow in recycled coco & perlite clean all the roots out i can get by hand . Throw fresh plants in no enzymes never had a prob.I think its the pond zyme too.. Or repot in fresh coco.. B

 

[Hydropimp]

How long have the girls been in the pots?

And what do the roots look like?

 

[Decisive]

How long have the girls been in the pots?

And what do the roots look like?

They've been in those pots for 3.5 weeks or so, the roots breaking out the bottom are thick white and fuzzy. They look very good, I am kind of tempted to not use anything like the pondzyme and just switch to something like dutch master zone to keep my rootzone completely sterile. While the roots look very good (at least what I can see breaking out of the pots) whats above ground is a different story.

Lights will be on in 15 minutes, I watered 6 hours ago (when dark cycle started) with 1ml /gal drip clean, 3/4 strength nutes (0.75 of the rezipe), no pondzyme this time just added some botanicare aquashield, aerated the solution with a 100 LPM air pump for an hour , pH'ed solution to 6.0 then pumped in about a gallon a pot. After the lights turned off I also foliar sprayed with magic green and cal mag. Will update with any changes but on the brightside when I watered 6 hours ago runoff from the pots had gone from 5.0 to 5.3 in some pots to 5.5-5.6 in all pots, looks like pH is coming back into range, hopefully everything bounces back.

 

[independent_1]

I think your getting some good advise here. I'm trying coco gh 6-9 now. Not experienced to give advise but when my plants starting dropping the same way I cut the cal-mg. Mixed my gh 6-9 formula in for 1 G of h20 and added another G of h20 basically 1/2 strength gh formula. Started watering in 2 times a day but only a little not to run off. They perked right back up. My guess is the nutes are building up in your medium. Advice to me was don't flush without keeping your ratios and ph exact.

 

[Hydropimp]

i just pick up some drip myself and some 35 % h202 food grade

you use chems so you can keep it sterile. my nova is almost done.

am taking the same route

 

[zeke99]

Any advice would be appreciated, thanks in advance

Yes. What matters to your plants is the quality of the water going in, not coming out. Stop measuring the runoff.

What are you using, RO or tap? If it's RO, than your problem isn't the water. You might be using the wrong fertilizer, but it's probably not even that either. If it's tap water, have you tested the alkalinity? If not, drop everything, go to a pet store and buy an inexpensive test kit that includes it. Test your water. If the alkalinity level is too high, i.e. way above 50 ppm, than it will raise the pH of your coco over the course of the grow. It's that simple. Maybe your problems are environmental and not related to the water or the ferts.

 

[ROOTZ]

Definitely drop the cal-mag