HYDRO looking for suitable pH buffer options.

[Malkavian420]

I'm pulling my hair out trying to maintain the pH of my Hydro rig and need help.
Our local municipal water is very hard (which means it has all those lovely trace nutrients like zinc, calcium, etc.), but its also very Alkali, measured at about pH 9 (the indicator solution goes dark blue).
The nutrients I use are the General Hydroponics "FloraGro", "FloraMicro" & "FloraBloom" - altho the "FloraMicro" is the version formulated for Hard Water.
So when mixing up a 5 Gallon bucket of Nutrients, once I have everything mixed I do adjust the pH done to around 6 before adding, and everything goes great!

BUT, on as previous grow my crop sufffered from Zinc lock-out and when I tested the pH it was down to 4, which was a surprise, but adjusted it back up and the plants thrived and bounced back almost immediately.

The current grow cycle, which started Labor-day weekend, I have been watching the pH level like a hawk!
the pH started of at pH 6 as I wanted it, but a week later when I measured again it had dropped to pH 5 after just one week! Adjusted it back up.
Tested it again a week later and it had dropped again to pH 5 - so I am getting concerned.

Does anyone have any idea what could be driving the pH down or what to look for?

Also, has anyone used and could recommend suitable (safe for food consumption I assume) pH buffer solutions?

[FlyingDutchPaddy]

once I have everything mixed I do adjust the pH done to around 6 before adding, ...

Hi Malkavian420 ,

I'm a hydro grower as well using GHE flora series.

I'm a little confused as to what i quoted above....

are you adjusting pH before mixing nutrients, or adjusting afterwards?

how are you mixing up your nutrients? adding each to the water, or mixing together first and then adding to water?

sorry for asking these Q's but it helps to understand what you do, and where it could be improved upon.

something i read on the european site for GH is that they advise to pH your water first to 5.5, before adding nutrients.
also, if you're using CalMag supplement you need to add that first before adding Micro.

But, as you have very hard water, maybe just Epsom salts for the Magnesium... there's a lot of calcium in the water already. Maybe no need for CalMag supplement that increases calcium even more.

I'll share what I know about my water source.

Its from a private well, pH is 7.5 , ppm (500 scale) is about 280.
Boiling a kettle of this water about 3 times leaves a noticable layer of limescale on the bottom heating plate.
Still, its free and thus cheaper than buying water in the shops (that can still have a high level of carbonates in it, also hard but slightly less, water). Make do with what i have.

In my preparation: water quantity 13.2 Gallons US.
after adding silicon (50ml of Vitalink Silicon Max - SiO₂ at 6% - used at 1ml per L), pH rises to around 8.5 - 8.7
adding about 17ml pH down (Vitalink pH down - 81% phosphoric acid) brings this down to around 5.7.

Then I add Fulvic acid and seaweed/kelp to help chelate.

Then I add in this order, CalMag, Micro, Gro, Bloom.
And I wait about 4 mins before adding the next dose.

pH afterwards is about 5.9 and it stays around there until next water change every 7 days.

Let us know about the questions.

[Malkavian420]

Hi, so I always do my nutrients in 5 Gallon "lots" using a 5G mixing bucket.
So I add 2 Gallons of water to the bucket first, then the "Micro", another Gallon of Water, then "Gro", another Gallon of Water followed by the "Bloom". And finally, the last Gallon of water with 'Hydro Guard'.
At this point, I pH test and adjust.

I also do a second pH test after I poured the nutrient/water mix into the reservoir to make sure it is in the pH5.5-pH6.0 range.
But when I check a week later, the pH drops to ph5.0.

Between each 'planting' all the reusable components (reservoir, air-stones, water pump etc.) are cleaned with boiling water and H2O2, and all non-reusable components (tubing etc.) are thrown out and new tubing etc. is cleaned and prepped.

Now we are currently having an "Algae Bloom" going on in Central TX, but I don't see any slime build-ups or any other signs of algae contamination, so I assume that the Hydro-Guard is doing its job.

With regards to the "pH down" - I have not seen anyway any documentation or formulas for how much to add per Gallon to adjust the pH by .5, so it had always been hit or miss.

Is it possible that the Hydro Guard because they consume/modify the nutrients that they could be changing the pH?

[RFheavy]

Depending on your bucket temps, a water chiller can help stabilize fluctuating PH. They have some for fish tanks that might be reasonable in price to you or you can get a heavy duty for a few hundred.

[dphipps1020]

I have the same issue. I just keep adding pH up to my water. As long as you keep in mind it takes a lot less pH down than it does pH up. I don't really feel like there's any real guidelines to follow with using them (of course I'm still fairly new to this) other than to adjust a little at a time and keep checking. Also, let your water sit for an hour between checks to allow time for adjustment. If you change your water about every month then you should only have to adjust a few times. Also, the range is 5.5-6.5 so if you're keeping it under 6 you don't have a wide buffer and will be adjusting constantly. I usually take mine right to the 6.5 mark and let it do its thing. My water is actually coming out right above 6.5 so I don't adjust when I change everything out. I agree it's probably the water temps cause it was worse for me when I had my HID lights going. I never got a water chiller so I'm not really sure. Also, get yourself an electronic testing meter (less than $10 on eBay) it will make things much easier. As far as the order to mix nutrients in I think the extra stuff is a personal preference, as long as you mix the trio Micro first. I do Micro, Gro, Bloom, CalMag, and then Hydroguard and haven't had any issues. Hope you get it figured out.

This may help - https://www.growweedeasy.com/wp-cont...-marijuana.jpg

[Malkavian420]

Thank you RFheavy - the water temp is on the high side, trying to keep the water temp in a reasonable range has been a challenge and so it has been warmer then it should. But then again, even indoors, this extreme summer has put quite the strain on the AC.
So I will look into an aquarium water chiller...

[FlyingDutchPaddy]

Hello

Malkavian420 , and other fellow growers,

As mentioned above, temperature does play a role in pH, but not that much.
temperature does have an influence on the microbes in the rootzone and water though, as well as light leakage.

i want to touch upon:
- mixing nutrients,
- usage of "pH down" solution,
- temperature (extended to dissolved oxygen),
- light leakage,
- water change intervals,

nutrients:
Malkavian, from what you describe on how you mix your nutrients, i think you can improve on that.

the first PDF that i attached from GHE (flora_series_for_all_plantes.pdf) mentions this, amongst others but the important ones are:
This chart is made for «normal» tap water, with the following characteristics: EC = 0.5 – pH of 8.0 adjusted to 5.5.
- For best solubility of mineral salts: before mixing adjust your pH level between 5.5 and 6.5. Control again after adding the nutrients. Verify your pH level regularly.
- Shake well before using. Flora Series is very concentrated. To avoid precipitation, never mix the 3 componnents together but pour each separately. Rince your measure between each component.

my understanding of this is that you are recommended to:
1) pH the full 5 Gal first to around 5.5 - 6.0,
2) add nutrients 1 by 1, and stir the water well between adding each nutrient,
3) measure pH again and correct up or down so that 5.5 <= pH <= 6.5

then you add hydroguard.speaking of, hydroguard should not influence pH as these are microbes, not mineral salts that can influence pH.

pH down:
there are various manufacturers who supply pH down.
GH has it as well.

in my experience, the GH pH down is not as concentrated or as stable as the one i use, which is from Vitalink.
10 Gal water would need around 35ml pH down from GH, and it would need around 10ml per adjustment in days after water change.
pH would climb up and i'd have to re-adjust it every day almost.

whereas it only needed 10 ml of the vitalink, and would drift around the intended pH for days and needed very little adjustment, if at all.

generally i would recommend, as stated as well by dphipps1020, add a little pH down/up stir a bit and measure. keep adding as needed until you get to the intended pH.
how much to add will depend on how concentrated your pH down/up solution is.

temperature:
it is recommended to keep the water temp between 18 - 22C for several reasons, but i list 2:
1 - 'bad' microbes don't like that temp, they prefer warmer.
2 - level of dissolved oxygen.

bad microbes increase the chance of root rot, which your hydroguard should protect for.

disolved oxygen is two-fold.
high levels of disolved oxygen are good for the roots
low levels of disolved oxygens are preferred by bad microbes.

the higher the water temperature, the less disolved oxygen it can hold.
the 'sweet spot' is around 18-20C.
higher than this creates the low oxygen warm environment that bad microbes love.
lower than this slows down the ability of the roots to take in water, nutrients, etc...

light leakage:
this is a problem in the root zone.
algea, amongst others, needs light for photosynthesis, and when they get it they will use up nutrients in the water, essentially competing with the plants.
with some searching online, you can find a lot more info about this.

water change intervals:
GH recommends (on GWE it's also mentioned for hydroponics) to change out water every 7-10 days.
leaving it for over a month or longer...
(yes, i've made that mistake as well in the beginning)

the 2nd PDF (GH_FloraSeries-REC_03216am.pdf) in the top left advises:
- temp below 24C (75F)
- change water every 7 - 10 days, top off with fresh water between changes,
- keep water aerated,
- pH between 5.5 - 6.5

and, it also mentions:
Which comes 1st, Armor Si or CALiMAGic?
• When using both Armor Si and CALiMAGic, add Armor Si to the reservoir 1st.
• When using Armor Si and/or CALiMAGic, with Flora Series, these products should be added prior to adding FloraMicro.

Silicon,
CalMag,
Micro,
Gro,
Bloom.
(microbes)

[Malkavian420]

Oh this is amazing... THANK YOU!!!!

[FlyingDutchPaddy]

i infer that you're using a water color solution compared to a chart to gauge the pH, having looked again at the first post.

i don't know about your budget, but might i suggest looking for a digital pH measuring pen? (search online shopping sites - you would look for "pH meter")
they can be found for fairly cheap ($30 could be average, you may find cheaper).

you may find that getting a TDS meter / PPM meter / EC meter is very much worth your while as well.
they measure the total amount of nutrients that are in the water. (and how hard your water is to start off with).
(if you start looking for this online, you'll start a wonderfully educating evening of consuming weed, reading online, learning...

[dphipps1020]

I got a pH tester and TDS meter combo for about $13 and they work great. Saves time, money and effort. I usually just fill a small bowl with water, prop my meter in for the pH and take care of other things while I wait for the meter to stop adjusting.

[quirk]

My city water has a ph of 8.1 and a ppm of 296. I use these citric acid crystals, 1/4tsp/gal to achieve and maintain 6.2-6.5 ph (organic soil grower) and it somehow lowers ppm to 194. I've had much better ph stabilization with the crystals as opposed to the phosphoric acid I used in the past.

[Tersky]

I wonder if the citric acid is neutralizing the chlorine in the water and lowering the ppm that way. Assuming you are using tap water

EDIT: Im slow....didnt realize how old this post was!

[alltatup]

I thought I wrote a response yesterday, but then I got high. In case nobody's said it: check pH daily. I usually have to adjust it daily or every other day. I check it every day.

[alltatup]

Organic357 man, I wish I'd been growing that long, but better late than never. I was referring specifically to situations where one knows there will be fluctuation (I grow hydroponically), but living soil (about which I know nothing) sounds delightful.

[Organic357]

Alltatup I started out in soil 6 years ago. Like a lot of newbies I went to the local hydro store and got Fox Farm soil and nutes. There were two big issues for me. One was having to mix up as many as 13 supplements with some of those being in quantities so small that I had to purchase a graduated eyedropper to measure them out. The second issue is that they would shoot my pH numbers all over the place.

With a living soil you get several benefits. First of all it is water only. Secondly no screwing with measuring out a bunch of nutes. Thirdly since it is soil it is pretty forgiving of mistakes. Fourthly if you screw up one plant you don't necessarily screw them all up. Fifth you don't have to flush. Sixth it cost a lot less over time. Lastly you can re-use the soil for easily up to three years unless you get something really bad in it. You should re-amend the soil but this is pretty simple and cheap. My grow will be 100% organic. This generally means longer lasting 'highs'. Currently I am growing Aurora Indica, Critical CBD, Misty Kush, Nebula CBD and Northern Light. Looking forward to the Aurora Indica as it is my first purp. Also growing under LED's for the first time.

Please don't take my comments on living soil as a put down of anyone else's preferred method. If people have a method that works for them and produces good safe bud more power to them. My concern is that Cannabis is definitely a heavy metals accumulator and after listening to the Cannabis Cultivation and Science Podcast which you can find at KIS Organics I have learned that a lot of companies selling nutes and soil do some things that are of concern to me. One last point, hydro looked very interesting and it produces some great product. It just seemed a bit complicated and with a water only living soil it makes things much easier for the person taking care of my plants when I am out of town for a week once a year.

[alltatup]

Organic357 That sounds awesome. I definitely love hydro and I give my plants a nice long flush at the end.

[Organic357]

I realize that I am responding late to this. I am growing in living soil and my water pH after filtering my tap water is ~7.5 - 8.1. I used to use EarthJuice pH products but recently moved to citric acid for pushing my pH down on the recommendation of the person who created the soil. I use Milliard Citric which I purchased on Amazon for $8.49 for a 2 pound bag. To drop 1 gallon of this filtered water by ~1 pH I used what I guesstimate is ~1/8 tsp of this citric acid.