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Anyone buffer their RO with calcium/magnesium carbonate?

BlackMagic66

New member
I am a hydro noob about to dive in :biglaugh: for the first time. I am going to be using RO water and I was wondering if anyone here uses calcium carbonate and magnesium carbonate to buffer their RO.


Is a 4:1 ratio going to be ok? How much CaCO3 and MgCO3 by volume do you add per gallon? Do you add aminos to chelate the Ca/Mg?


This is going to be my base for a recirculating coco grow with a live rootzone, so at the least I am also adding molasses for the bennies and 1/4 strength aquaflakes due to using coco as my medium.
 

Douglas.Curtis

Autistic Diplomat in Training
15+ years using R/O and hydro.


My advice? Don't buffer your r/o, and keep molasses out of your hydro.


Find a complete nutrient mix, one which includes enough calcium already, and mix appropriately. You **want** your pH to swing through the full healthy range for cannabis. Keeping your pH constant through over-buffering will require you to use higher strength nutrients, and will also lower your quality.


Welcome to ICMag!! :D
 

Douglas.Curtis

Autistic Diplomat in Training
Happy to help. :)

As for the replacement for molasses, you're not in soil so there is no beneficial food web to feed. Adding sugars only sets you up for any bad things you happen to encounter to bloom with great speed. Get Great White or similar, and use it before transplanting to their final destination.
 
U

Ununionized

Exactly what Doug's sayin BM. They're called carbon feeding bacteria and your carbohydrates will feed em and what they'll do is form this gelatinous slime, all over the surfaces of everything that stays constantly wetted by your water.

If you intend to ramp up the calcium in the water, some people dilute their RO with tap, to about 60 ppm I think is the number I saw a couple of people who claimed to have their reasons, sticking to as a max.

I think what happens is when you get more than about 60 ppm rise due to adding the tap, -there's a dash of chlorine in it too,

light doses of ferts, don't drag the pH down to the point where most of your minerals stay dissolved.

Doug is definitely telling you the truth about laying off that sugar, the things that cause the slime are formally the carboniferous bacteria and they will grow slime all over everything including your roots. They'll cover your roots like some kinda plague from a Star Trek movie. The slime tends toward being clear with various tintings.

Your magnesium's gonna be augmented with Epsom's Salt, which dissolves pretty readily, if you decide to start patching little improvements on your nutritional profiles.

Most hydroponic growing has to be what's called the sterile type,due to the carboniferous and some other bacteria that'll make slime on things. Generally by the time the slime is spreading everywhere you're noticing it on the non living material first, and it's awhile until you realize that yep, it's growing on the roots too, and you have to deal with a bunch of ever escalating troubles depending on how bad you overload the water with carbon.

The gel they make is designed to create a buffered area where the bacteria can thrive and this includes exclusion of oxygen, so - the roots take the hit immediately, and the plants will die if that slime's allowed to remain in place on them.
 
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U

Ununionized

I never really have done a hydroponic living root system like that so I can't tell you I've got someone's reservoir in mind when I was talking about those carboniferous bacteria making slime, I guess since you're just gonna drip through, there's a lot of oxygen but I've never done it.

I've grown some plants in surprisingly wet, sopping coco and - also surprising, the root rot was a long time coming on, I had some become an experiment one time due to a sprinkler flooding them and I just let them sit in the water till I saw problems I was surprised enough, that lol - I remember I was surprised, but it was only one experiment and the plants had collapsed from lack of oxygen a relatively long time before those roots started getting rot. It wasn't the first thing I noticed happening. Thinking back about it there were no sugars either. They were nourished salts-only.

I wasn't trying to throw you off your whole game, I just haven't ever seen many or maybe any, living coco buckets.

I know such things exist, I just never did it. I thought there were problems being able to keep the sweetened water from developing critters.
 

BlackMagic66

New member
I have read quite a few grow journals of folks inoculating their Coco with stuff like Great White or OGBiowar, and I just sort of gravitated towards the idea of a living root zone to promote root growth than a $90 bottle of root simulator.


In most of the journals I read, they seemed to be using enzyme treatments like pondzyme and the like in their rez rotations, but I honestly have no clue if that helps with the slime.



It seems like most folks here are recommending a sterile hydro environment though...
 

Douglas.Curtis

Autistic Diplomat in Training
I've run hydro for 15+ years and I don't do a sterile res. I start a new res at the beginning of flower and do not change it out until 5 days before harvest. My nutrient solution stays crystal clear till the end.

My secret? Temps, cleanliness and minimal use of additives and things from 'biological' sources.

Keep your temps low for roots-in hydro like DWC, NFT, RDWC and any system where the roots are constantly exposed to the nutrient solution. I keep my res between 65F and 69F, constantly. Roots-out systems like E&F or intermittent drip can handle much higher res temps, though I don't recommend above 75F if you can help it.

Keep stuff from falling in the res, like leaves and media. The only 'biologically' derived additive I use is Floralicious+, and I use less than 2ml/gallon. NPK/Micros, some epsom salt and a TINY bit of silicon.


:tiphat:
 

Ganoderma

Hydronaut
Mentor
Veteran
I am a hydro noob about to dive in :biglaugh: for the first time. I am going to be using RO water and I was wondering if anyone here uses calcium carbonate and magnesium carbonate to buffer their RO.


Is a 4:1 ratio going to be ok? How much CaCO3 and MgCO3 by volume do you add per gallon? Do you add aminos to chelate the Ca/Mg?


This is going to be my base for a recirculating coco grow with a live rootzone, so at the least I am also adding molasses for the bennies and 1/4 strength aquaflakes due to using coco as my medium.

Some times I go and add a gallon or two of normal tap water into a 30 gallon RO storage tank. That tends to make my RO water more PH stable. Having some dissolved minerals in the RO does make my mixed nutrients solutions more stable, from what I've seen over the years.
 

Douglas.Curtis

Autistic Diplomat in Training
Some times I go and add a gallon or two of normal tap water into a 30 gallon RO storage tank. That tends to make my RO water more PH stable. Having some dissolved minerals in the RO does make my mixed nutrients solutions more stable, from what I've seen over the years.
The downside to this is you don't want stable pH when growing cannabis. The other downside is you're adding (usually) un-necessary elements for growth, which the cannabis absorbs and stores anyway. This degrades quality.


You want to drop your pH with nutes, then allow the plants to use the nutes and have a slow pH rise. The root zone pH needs to be within the healthy range, which for cannabis hydro is around 5.3-6.1, depending on your system/environment/strains. The speed this happens depends on the res size, in comparison to plant numbers and light source. ;)



The more stable your pH, the stronger the nute concentration has to be for healthy plants. The stronger the nute concentration, the more the hyper/dynamic accumulator feature of cannabis ruins it's own quality. Cannabis can and will absorb excess nutes in the root zone, and pack it away in the flowers where it will not flush out.



You want the cleanest, tastiest, most resin rich cannabis? Shoot for a full pH swing and as close to underfeeding them as possible. :D
 

Ganoderma

Hydronaut
Mentor
Veteran
The downside to this is you don't want stable pH when growing cannabis. The other downside is you're adding (usually) un-necessary elements for growth, which the cannabis absorbs and stores anyway. This degrades quality.


You want to drop your pH with nutes, then allow the plants to use the nutes and have a slow pH rise. The root zone pH needs to be within the healthy range, which for cannabis hydro is around 5.3-6.1, depending on your system/environment/strains. The speed this happens depends on the res size, in comparison to plant numbers and light source. ;)



The more stable your pH, the stronger the nute concentration has to be for healthy plants. The stronger the nute concentration, the more the hyper/dynamic accumulator feature of cannabis ruins it's own quality. Cannabis can and will absorb excess nutes in the root zone, and pack it away in the flowers where it will not flush out.



You want the cleanest, tastiest, most resin rich cannabis? Shoot for a full pH swing and as close to underfeeding them as possible. :D

You must know, I do disagree with about half (or a little more) of what you say about hydroponic growing. But that is my point of view...

1. the desired PH range of your nutrient solution depends on your medium that your plants are growing in. The PH range that you state is too low unless you are growing in rockwool. Even Jorge Cervantes states a higher PH range in his books that I've read. If i recall correctly, he stated 5.8-6.5 as the IDEAL range for hydroponics nutrients.

2. having the staring RO water more stable prevents larger ph swings in your mixed nutrients. A small swing in PH is good for the plants, but not the larger swings.

3. Have you ever had your nutrients solution's PH to drop or to raise out side of your desired PH range. When you add your PH up or PH down, it brings your PH into your PH range. But then the next day it's swung back to where it was before adding in you PH adjusters. Adding in that little bit of tap water into you RO water before helps to buffer that water and it makes the mixed up nutrients PH to be more stable so it doesn't make large swings.

4. If you have 30 gallons of RO water in the 0-15ppm range and add in (1-2 gallons of) tap water that has a ppm of 120 per gallon, that doesn't add much extra dissolved solids into the water once you do all the math (if you do the math).

5. it reduces the amount of PH adjusters I have to add into nutrients solutions during the "life span" of that reservoir (life span = until the nutrient solution is change with fresh mixed nutrients)

6. The older a plant is with a larger root system (not including rockwool) I've seen them able to handle a larger PH range. Most often it's a PH range that is 0.5 to 0.75 higher and the plants handle it like it was nothing (I've noticed this in veg)

7. You sound a little rigid in how you've grown all these years, in the form of how you seam to sound when mentioning/stating ways of doing things from your experience.

8. The OP was just asking about buffering RO water by adding in stuff that will dissolve into the mix, not a run down of this or that issue within the whole realm of hydroponics outside of buffering your RO water.
 
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Douglas.Curtis

Autistic Diplomat in Training
You must know, I do disagree with about half (or a little more) of what you say about hydroponic growing. But that is my point of view...

1. the desired PH range of your nutrient solution depends on your medium that your plants are growing in. The PH range that you state is too low unless you are growing in rockwool. Even Jorge Cervantes states a higher PH range in his books that I've read. If i recall correctly, he stated 5.8-6.5 as the IDEAL range for hydroponics nutrients.
I said pH in the root zone. Jorge is talking about reservoir pH. Big difference. I disagree with Jorge on a lot of things. ;)

Y
2. having the staring RO water more stable prevents larger ph swings in your mixed nutrients. A small swing in PH is good for the plants, but not the larger swings.
pH swing is controlled by reservoir size, as I previously mentioned. Your swing should happen within 7-10 days for Roots-In hydro. Roots-Out hydro (media) still requires a slight pH variance, in addition to the pH changes they have between waterings, which is why recirculating systems are easier to dial in.

Y3. Have you ever had your nutrients solution's PH to drop or to raise out side of your desired PH range. When you add your PH up or PH down, it brings your PH into your PH range. But then the next day it's swung back to where it was before adding in you PH adjusters. Adding in that little bit of tap water into you RO water before helps to buffer that water and it makes the mixed up nutrients PH to be more stable so it doesn't make large swings.
The only pH drops I have are due to root rot, when I let environmental conditions get out of whack. Nothing to do with a properly run res.

pH going up too fast? I've been doing this for 15+ years and the only pH up (out of control) has been due to pumping too much air through a roots-in system. I use res size to control pH rise. It's rock solid predictable when you use r/o only.

Y4. If you have 30 gallons of RO water in the 0-15ppm range and add in (1-2 gallons of) tap water that has a ppm of 120 per gallon, that doesn't add much extra dissolved solids into the water once you do all the math (if you do the math).
Cannabis is a hyper/dynamic accumulator plant. This means it can and will absorb elements it has zero need for growth. The highest quality cannabis is created when the plant has access to only nutrients it can use, in appropriate amounts as they're needed. "Tap Water" is as infinitely variable as the cannabis plant is. If you want the best quality, start with the purest water. ;)

Y5. it reduces the amount of PH adjusters I have to add into nutrients solutions during the "life span" of that reservoir (life span = until the nutrient solution is change with fresh mixed nutrients)
I add pH up *once* during flower, and this is when I mix the initial reservoir. Plants use nutes, pH goes up. Add nutes back, pH goes back to starting point. Lather, rinse, repeat until the fade. There is no need for continually adjusting pH.

The only time I change my flowering res is 5 days before harvest, with pure, un-pH'd r/o.


Y
6. The older a plant is with a larger root system (not including rockwool) I've seen them able to handle a larger PH range. Most often it's a PH range that is 0.5 to 0.75 higher and the plants handle it like it was nothing (I've noticed this in veg)
Nutrient solution pH, or pH in the root zone? Again, a huge difference. Your input pH is always going to be variable according to your setup and plants. The root zone pH is what you're attempting to control.

Y
7. You sound a little rigid in how you've grown all these years, in the form of how you seam to sound when mentioning/stating ways of doing things from your experience.
Though I've used the base lucas formula for 15+ years, it's only a base nutrient. The res management methods I use have only become more strict, as my research into quality has advanced. I've only come across the same quality I grow once, and that was in 2008. It was also an epiphany which started my research, and eventually my book on the subject.

Y
8. The OP was just asking about buffering RO water by adding in stuff that will dissolve into the mix, not a run down of this or that issue within the whole realm of hydroponics outside of buffering your RO water.
As far as I'm concerned, cannabis quality and what you do to your water go hand in hand. When you've had superior quality fudge or espresso, do you ever look at those nasty chunks of fudge at gas stations or Starbucks the same way again? The answer is a resounding "No."

:tiphat:
 

Ganoderma

Hydronaut
Mentor
Veteran
Though I've used the base lucas formula for 15+ years

I tried that "Lucas formula over 20 years ago" back when Lucas was on Over Grow and every one was going all goo goo gagga crazy over it like a teenage girl being all emotional and it (Lucas's mix ratio for what is suppose to be a three part nutrient line) sucked hard big time back then!!!

So I would disagree with the use of that formula for GH's nutrient line. GH works great for veg growth.

Technaflora beats GH nutrients in any form for flowering plants any day. it may cost a little more, but the proof is in the flowers.


Now can we get back to the OP's topic of buffering RO water.

OH by the way I'm the ICmag mentor for hydroponics just to let you know where I'm coming from!
 

Douglas.Curtis

Autistic Diplomat in Training
I tried that "Lucas formula over 20 years ago"
It didn't work for you, because you obviously didn't use the proper res management methods. The two go hand in hand, or you get problems. You **must** have a full pH swing or you get deficiencies with Lucas. ;) This is Tsue at 19 days into flower, do you see deficiencies? The ppm was less than 700ppm.



Now can we get back to the OP's topic of buffering RO water.
Proper hydro has everything to do with why you don't want to buffer your r/o.I'm still **very** on topic here.

OH by the way I'm the ICmag mentor for hydroponics just to let you know where I'm coming from!
As a mentor to others, I highly recommend you look into using a full pH swing. It will significantly increase the quality of your cannabis, while it will also make hydro **much** simpler for you.

:tiphat:
 

BlackMagic66

New member
Great info to sift through here folks!


A few other points that might change the focus here....


I am running a recirculating EnF system with CoCo and using aqua flakes as my base nutes.


Due to the way coco interacts with Ca and Mg most coco specific nute lines increase the amount of of Ca and Mg. Since I am NOT using a coco specific base nute, adding a bit of Ca and Mg back into the RO as both a buffer and to bring the Ca/Mg back to tap water level should be better?


Also, I am not adding any % of tap water back because I have pretty polluted tap water, and also I am using capulators and not want to introduce any chloramine to the system.
 

Douglas.Curtis

Autistic Diplomat in Training
Your goal is to provide a balanced mix of nutes for your plants and setup. Definitely add what you need for your res, when you're mixing your res. :)
 

Douglas.Curtis

Autistic Diplomat in Training
This is a thread that is a a sticky thread at the top of the hydroponics form.

https://www.icmag.com/ic/showthread.php?t=23357

It's a big read, but BigToke covers the topic(s) of buffering the water. This is relevant to the OP's question about the buffering of water.
BigToke advises a steady pH and does not recommend r/o water. In my opinion, this method grows inferior cannabis.


He definitely does a great job at explaining how to buffer your tap water correctly for steady pH. Considering tap water is nearly infinitely variable, he does a great job breaking down how to deal with it. :) Very well done. Anyone can also use this information to buffer their r/o water, if that's the route you're going to choose.
 
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