Need some advice on this plant

[MrMojoRisin]

Vermiculite ph is neutral from what I recall? Is it a wast to drain system?

>>> If your runoff pH is higher than your starting (water) pH, use this equation to determine your soil pH:*
Soil pH = Runoff pH + Difference

If your runoff pH is lower than your starting pH, us this equation:
Soil pH = Runoff pH - Difference.

For example, say your the starting pH of your solution before it goes in is 6.5 and the pH of your runoff is 7.0. The difference is +0.5, so using the above equation:
Soil pH = 7.0 + 0.5*
Soil pH = 7.5

If your starting pH is 6.5 and your runoff is 6.0, your difference is -0.5 and using the above equation:
Soil pH = 6.0 - 0.5
Soil pH = 5.5


Which makes your medium around 8.4 so with that your locking out,

Thanks GA66 for the informative reply. It is a drain to waste system.

I've read somewhere that Vermiculite actually can have affects on pH. I thought it was neutral going into this grow. Apparently the oyster shells or something make it alkaline and it varies wildly from batch to batch depending on where ingredients were sourced.

My confusion is that I rinsed the hell out of it after finding the runoff so high, so I don't understand at all why it sits so high. The medium itself (i'm hoping) is holding that properly pH'd water for awhile and getting it to the roots.

Do you have any recommendations on a course of action? I'm thinking of dumping the res, flushing, and adding a ton more pH'd water.

As far as the 5.5pH i've been aiming for...... i originally was going to add at 5.8pH, but was advised that the res will raise in pH pretty quickly and that a 5.5pH would be better. Any thoughts on this?

 

[Grey Bear]

Waxi, may be a better source for advice on this one. I have not used hempy buckets myself.
I do not fret much myself over strange leaves early on.
That being said, I tend to blame splash burn for mystery leaf damage at this size.
Water on the leaves during lights on or in sunny conditions can leaves marks like that.
Pay attention to the new growth and see what happens, avoid drastic changes.

 

[Waximus]

Howdy, Mr. Mojo
My experience is with DWC and coco/drip systems, primarily. That said, it sounds like you might have some vermiculite that is is indeed spiking your pH. The last pics you posted, to my eyes, look like a calcium deficiency- likely due to the pH being so high.
I would keep feeding with a lower pH, and monitor the runoff to see if it stabilizes in a lower range. Using Goauto's math, you will want to figure out what pH needs to go in, based on the runoff check.
One question: Can you get the temperature of the liquid in your hempy? It could point to other reasons for this issue.

 

[MrMojoRisin]

Howdy, Mr. Mojo
My experience is with DWC and coco/drip systems, primarily. That said, it sounds like you might have some vermiculite that is is indeed spiking your pH. The last pics you posted, to my eyes, look like a calcium deficiency- likely due to the pH being so high.
I would keep feeding with a lower pH, and monitor the runoff to see if it stabilizes in a lower range. Using Goauto's math, you will want to figure out what pH needs to go in, based on the runoff check.
One question: Can you get the temperature of the liquid in your hempy? It could point to other reasons for this issue.

Thanks @Waximus I've been watering with water that is at room temeperature-ish, left out overnight on my balcony. i'd day 75 F average, maybe a little warmer at times. I've added just a touch of EJ CalMag to my feeding today to try and help that Calcium.

i did another run through and have the runoff ph comfortably at around 6.2. That is a big step down from where it was, and it took many many flushing to get it there. i will continue to add pH water at around 5.2 wit each watering and each feeding, hoping that it will keep coming down.

i wish i had done a bit more research on Vermiculite beforehand, but i did not realize it had a dark side until i had a problem. Live and learn as they say. Hoping it does not completely wreck this grow.

 

[Waximus]

Thanks @Waximus I've been watering with water that is at room temeperature-ish, left out overnight on my balcony. i'd day 75 F average, maybe a little warmer at times. I've added just a touch of EJ CalMag to my feeding today to try and help that Calcium.

i did another run through and have the runoff ph comfortably at around 6.2. That is a big step down from where it was, and it took many many flushing to get it there. i will continue to add pH water at around 5.2 wit each watering and each feeding, hoping that it will keep coming down.

i wish i had done a bit more research on Vermiculite beforehand, but i did not realize it had a dark side until i had a problem. Live and learn as they say. Hoping it does not completely wreck this grow.

It sounds like you've got the pH stabilized, so let's keep an eye on it and hope its sorted, then

I never used vermiculite. I'd read it compacted, and could frig with pH, and just used perlite for a long time. Recently, someone gave me some rice hulls, at a grow open house, and the RICE HULLS work better than either perlite OR verm. Of course, I think it'd get kinda porridge-like, in a hempy lolol As an amendment, it pretty much rocks, though!
Have a great weekend, MMR Let us know how it goes.

 

[Happy Horticulturist]

Before using a medium for hydro I always wash it, then let it soak in pH 5.5 for at least 24 hours. I'll check the pH hasn't changed. If it has, drain it and fill it up with new pH 5.5. I find this stabilises things. Especially with clay pellets.

I've grown a hydro grow in Perlite and Vermiculite once, it was a basic flood and drain. It went really well.

However saying that I don't see the point in using Vermiculite in hydro or at all, unless you're unable to water them regularly. Perlite though is great, provides lots of air to the roots.

 

[MrMojoRisin]

Before using a medium for hydro I always wash it, then let it soak in pH 5.5 for at least 24 hours. I'll check the pH hasn't changed. If it has, drain it and fill it up with new pH 5.5. I find this stabilises things. Especially with clay pellets.

I've grown a hydro grow in Perlite and Vermiculite once, it was a basic flood and drain. It went really well.

However saying that I don't see the point in using Vermiculite in hydro or at all, unless you're unable to water them regularly. Perlite though is great, provides lots of air to the roots.

Yes, i agree. I will be using just Perlite in my next grow. It is generally stabilized now, but no joke it took at least 5-6 Gallons of ph'd water for each bucket run through to get it there.

 

[Happy Horticulturist]

Yip. The clay pellets are like that too. I generally put them in a big 25 litre bucket with a pH or about 5.0.. they generally raise the pH to 6.0.. then I add some more pH down to 5.5.. see how it sits.

I find that one of those waste paper baskets with all the holes in the sides is GREAT for this job. One bucket to hold the medium soaking for many hours. Then the waste paper basket with holes to use as a giant strainer.

Like this

http://images.lookagain.co.uk/is/image/OttoUK/lg/waste-paper-basket~25S116FRSP_COL_BLACK.jpg

 

[Happy Horticulturist]

Sorry here's the waste paper basket I use for draining my medium after pH soaking.