Calcium hypochlorite rates

[dboi87]

I had originally posted this in the cannabis infirmary section but can't figure out how to delete a post. I figured this is a better spot.

I keep reading all over multiple forums that a solid way to keep your reservoir clean, is by using calcium hypochlorite.

The recipe says to make a stock solution of 1g to one gallon of water. The stock solution is then mixed at 6ml/gal (or 1fl oz for 5 gallons).

That breaks down to 0.0015625 grams per gallon.

However, looking around camping and survival forums, the same calcium hypochlorite is used to treat water in an emergency to make sure it is safe for human consumption.

The recipe for the drinking water says to make a stock solution of 7g of the calcium hypochlorite to 2 gallons of water. That stock is then mix at a ratio of 1:100 stock solution to water.

That breaks down to .035g per gallon.

That means the concentration of calcium hypochlorite is 22.4 times stronger for drinking water than it takes to keep your reservoir clean...

This doesn't seem to add up to me. Does anyone have any actual experience with the reservoir solution and rate recommendations based on real life experience

 

[excon]

i always give enough buffer and then narrow down the dosage - you want to start with the 0.0015 and increase if you see problems

i ll try to stay away from any conditioning and only add if absolute needed

 

[Ca++]

I'm having a crack at this shock business.
I'm using unstabilised calcium hypochlorite. This is 65%+ available chlorine.
There is stabilised, which means UV resistant, for outdoor pools. This pool specific treatment can easily contain 50% of useless stuff. I'm just not interested.

I'm buying 100g, to put in 3L as my stock solution. This will be used at 1ml per 10L, to give a 2ppm lift in chlorine.

The world health people say drinking water should be 5ppm max. UK water tends to be 1ppm. A grower here has used 6ppm. 2ppm is the recommendation I have seen floating about.

Can anyone save my crop, before I kill it

 

[Hiddenjems]

I'm having a crack at this shock business.
I'm using unstabilised calcium hypochlorite. This is 65%+ available chlorine.
There is stabilised, which means UV resistant, for outdoor pools. This pool specific treatment can easily contain 50% of useless stuff. I'm just not interested.

I'm buying 100g, to put in 3L as my stock solution. This will be used at 1ml per 10L, to give a 2ppm lift in chlorine.

The world health people say drinking water should be 5ppm max. UK water tends to be 1ppm. A grower here has used 6ppm. 2ppm is the recommendation I have seen floating about.

Can anyone save my crop, before I kill it

Without a sensor and automatic dosing it’s next to impossible to hold a consistent 1-2ppm chlorine.

Things can be going great but then some bad guys start a little colony. All of a sudden chlorine drops until you’ve oxidized them. It’s really easy to over shoot chlorine levels when this happens. You add chlorine and it doesn’t go up, next thing you know it’s 8-10ppm.

 

[Rexel]

I'm having a crack at this shock business.
I'm using unstabilised calcium hypochlorite. This is 65%+ available chlorine.
There is stabilised, which means UV resistant, for outdoor pools. This pool specific treatment can easily contain 50% of useless stuff. I'm just not interested.

I'm buying 100g, to put in 3L as my stock solution. This will be used at 1ml per 10L, to give a 2ppm lift in chlorine.

The world health people say drinking water should be 5ppm max. UK water tends to be 1ppm. A grower here has used 6ppm. 2ppm is the recommendation I have seen floating about.

Can anyone save my crop, before I kill it

Regular bleach (sodium hypochlorite) is cleaner in practice since its manufacturing process work towards being as pure as possible without leaving any residues when cleaning bathroom floors etc.

If you look at the chemical structure of the molecule the sodium part is minute compared to the hypochlorite side. I would even argue that sodium hypochlorite intended for cleaning floors contain less sodium than "Pool Shock" calcium hypochlorite that's often only 55-65% pure and intended to sterilize pools. The rest is sodium chloride and other impurities left from the manufacturing process.

For me it doesn't make any sense to use Pool Shock when regular unscented bleach is readily available at any Supermarket with listed concentration?

I've always used this dilution calculator:http://foodsafe.ca/dilution-calculator.html

Here's recommendations for running bleach in hydro/water cultures:

0.5-1ppm is recommended for Aero

1-2 ppm is recommended for Soilless/Coco Coir

3-5 ppm is recommended for DWC and flood tables.

Chlorine strips and meters doesn't work properly at the concentrations used and intended for hydro. You can simply go by smell and re-apply every 3-4th day in a nutrient reservoir. Residual effect of bleach is about 3-4 days depending on plant size and count.

Hope that helps!

Cheers!

 

[Ca++]

I have used bleach, but it's contents list wasn't all that revealing. As a cleaning product, like pool shock, it didn't have to be as transparent as lab supplies.
I have one here. The hypochlorite is made by mixing the hydroxide with chlorine. Hydroxide being caustic soda. This remains the main ingredient, and is just fine for cleaning the toilet, and keeping the 1.05% sodium hypochlorite stable.

I spent a tenner on 100g, including postage. This could make 10L of that 1% (<5%) bleach. Without the caustic soda playing such a part.
I'm not thinking it's a great idea to be handling this powder. Some liquid bleach is more appealing from that viewpoint. It's toilet cleaner though. I did get some baby bottle cleaner (milton) who's active ingredient was sodium hypochlorite, and they said the bottles can be used without rinsing. That might be worth a closer look, but that level of product, has baby tax added.

I'm invested in making the best product I can, so with nothing to save, I don't see a reason to not use the purest product I can.



It's use, and the timing of that use specifically, is a good topic to be sharing. My strips were useless, and my meter a nightmare to maintain. I learned nothing from them. My goal, is presuming whats in the tap, and boosting it 2ppm. Then just treating the top-up similarly. Rarely adding more, though at 4-5 days, it likely has gone. I just wish to maintain a clean looking tank in my F&D, and to know my reuse of substrate isn't breeding anything at an alarming rate. The plants can cope with a lot, but I don't want them to have to. Tank cleanliness is a great guide.


Amusingly, I have done this before, but got it wrong, and used calcium chloride. A Ca increasing route, that should offer no cleaning. Yet, it did. It even produced the smell of working. Which needs addressing. The chlorine levels we are talking about, are not something we can smell. It's not a method of judging it's levels in a tank. If you can smell something, then the chlorine is producing byproducts by working on (probably) organic matter. This is a sign it's being reduced, rather than one it's present. This can offer diagnostic info. If I make my 3ppm tank, and smell nothing, that is good. If instead I get a smell some time later, I had stuff in the tank the chlorine acted upon.

 

[Rexel]

I have used bleach, but it's contents list wasn't all that revealing. As a cleaning product, like pool shock, it didn't have to be as transparent as lab supplies.
I have one here. The hypochlorite is made by mixing the hydroxide with chlorine. Hydroxide being caustic soda. This remains the main ingredient, and is just fine for cleaning the toilet, and keeping the 1.05% sodium hypochlorite stable.

I spent a tenner on 100g, including postage. This could make 10L of that 1% (<5%) bleach. Without the caustic soda playing such a part.
I'm not thinking it's a great idea to be handling this powder. Some liquid bleach is more appealing from that viewpoint. It's toilet cleaner though. I did get some baby bottle cleaner (milton) who's active ingredient was sodium hypochlorite, and they said the bottles can be used without rinsing. That might be worth a closer look, but that level of product, has baby tax added.

I'm invested in making the best product I can, so with nothing to save, I don't see a reason to not use the purest product I can.



It's use, and the timing of that use specifically, is a good topic to be sharing. My strips were useless, and my meter a nightmare to maintain. I learned nothing from them. My goal, is presuming whats in the tap, and boosting it 2ppm. Then just treating the top-up similarly. Rarely adding more, though at 4-5 days, it likely has gone. I just wish to maintain a clean looking tank in my F&D, and to know my reuse of substrate isn't breeding anything at an alarming rate. The plants can cope with a lot, but I don't want them to have to. Tank cleanliness is a great guide.


Amusingly, I have done this before, but got it wrong, and used calcium chloride. A Ca increasing route, that should offer no cleaning. Yet, it did. It even produced the smell of working. Which needs addressing. The chlorine levels we are talking about, are not something we can smell. It's not a method of judging it's levels in a tank. If you can smell something, then the chlorine is producing byproducts by working on (probably) organic matter. This is a sign it's being reduced, rather than one it's present. This can offer diagnostic info. If I make my 3ppm tank, and smell nothing, that is good. If instead I get a smell some time later, I had stuff in the tank the chlorine acted upon.

Whatever floats your boat man. It seems like re-inventing the wheel for no reason or gain in my book?

You know the application rate is 0.5-5 ppm residual chlorine? Whatever dirt or sodium is in the local bleach it can't and won't affect plant growth negatively in any sense of the word, that's only in your head. Our local bleach brand even list it's purity content as being at least 98% pure.

Plants can't differentiate or care where the mineral content comes from, thats what humans do.

 

[Ca++]

We have been using calcium hypochlorite in water treatment for over 100 years. This thread is just about dosing it. Nothing new. No trying to use household cleaners, as you suggest.

Your use of sodium isn't only in my head. It's only in yours. Nobody else has said a thing about it. Bleach might be a short walk away, but mine is near 4x more hydroxide than hypochlorite. Michigan made that mistake. I'm not aligning with that. People don't even do that to their pool.

I'm not reinventing something. I'm doing it by the book. You make such a backwards argument, I would like to see this bleach. 98% pure toilet cleaner. It has to be Californian.

 

[Absorber]

I use bleach in my setup too

 

[Ca++]

Bleach doesn't exist. It's not a thing. https://en.wikipedia.org/wiki/Bleach

Calcium Hypochlorite exists.

That's quite a fundamental difference. It's why we have directions for water treatment with one, but not the other.

 

[Absorber]

Bleach doesn't exist. It's not a thing. https://en.wikipedia.org/wiki/Bleach

Calcium Hypochlorite exists.

That's quite a fundamental difference. It's why we have directions for water treatment with one, but not the other.

 

[Hiddenjems]

What he’s saying is bleach doesn’t come with a guaranteed analysis.

 

[Ca++]

What he’s saying is bleach doesn’t come with a guaranteed analysis.

It's a bit worse. A bottle of bleach, doesn't need to contain any specific chemical. It just needs to offer a bleaching action. We want chlorine from it, but it doesn't need to have any at all.
Hydrogen peroxide, for example, is a bleach.

Their is only a general assumption that sodium hypochlorite will be present.

That's not a strong argument for using it. I can't write out a recipe using bleach, to introduce a specific amount of chlorine.



White King
Chemical Name CAS Number Proportion %
Sodium Hypochlorite 7681-52-9 < 4.9
Sodium Hydroxide 1310-73-2 < 2
Coco Dimethyl Amine Oxide 70592-80-2 < 1

That last one, that might be 10% of the active ingredients, is a very toxic surfactant. It's not one we would choose as a wetting agent. It won't be compatible with some chelation. It might aid the 20% caustic soda though.
70% of the active ingredients are what we want, if you accept adding sodium.


As much as I'm not interested, others are, so I looked at available chlorine levels. I couldn't see anything over 15% in any grade. The calcium hypochlorite is 65% available chlorine. I had thought them on a level pegging, when looking how many bottles my 100g would make. It seems they are nowhere near equal though.
On my fingers here, if 70% of white kings active ingredients contain 15% useful chlorine, then the overall available chlorine in it's active ingredients, is about 10%. This leaves 90% of the active content, as unwanted. In the case of Calcium Hypochlorite, 35% is unwanted. However, it's Calcium. Is Calcium not better than caustic soda or lathering ingredients. Ultimately, is it worth paying more, to use bleach.
I'm not sure what <4.9% really means, but I do know my bleach is 1%. This gap between products, is making bleach a nondescript product. Even if it does actually contain some chlorine (which is likely does, though isn't at all guaranteed)


If someone wants to offer there recommendation of bleach mixing, and what their bleach actually is, then that could be a set of directions others can follow. I don't think it will stand up to scrutiny though. Calcium Hypochlorite is for drinking water treatment. It's the cheapest option, and adds only Calcium and Chlorine unless you are really cheap and buy pool treatment. Introducing uncertainly. Which is pages more to just say it's absurd

 

[Ca++]

I have put the brakes on this. I suggest for now, that nobody tries to make a stock solution. It seems that once wet, the calcium and chlorine split far to readily, for any sort of storage. The resulting stock solution, may be little more than a chlorine gas generator. I have mixed mine, and used it, but feel the best way forward from here, is to get it out the house until such time it's gassed off enough to pour it away.

It's a shame we don't have someone that actually did chemistry here.

The stuff did come as prills. Little pieces of fairly uniform size, that other users count into their tanks. It's nasty to handle, but I might keep some about. Today my 70L tank took 0.25g which is manageable.

 

[G.O. Joe]

It's a shame we don't have someone that actually did chemistry here.

Chemistry is in the doing, yes. Good thing I'm not here to tell about all the fun things I've done with hypochlorite and hypobromite, but you don't have to practice chemistry to figure out that HTH is reactive and very much not shelf stable unless it's the tropical bleach type. Since there's no one here I guess it's pointless for anyone to mention that it would rather be calcium carbonate or hypochlorous acid. Or that containers of dilute alkaline solutions free of metals and in the dark are much more stable than otherwise, much less pointing out that adding HTH to water is free of drama and storing the solid product next to something rustable is well known to be an excellent way to make rust.

 

[Ca++]

HTH? You might need to remember your audience.
I'm reading stock can be kept up to 2 months, and mine is well packaged, in the cold and dark. I never really know who is doing the talking though, and I don't like uncertainty. I will move forward with further use and testing, but can't suggest others do.

 

[Hiddenjems]

I have put the brakes on this. I suggest for now, that nobody tries to make a stock solution. It seems that once wet, the calcium and chlorine split far to readily, for any sort of storage. The resulting stock solution, may be little more than a chlorine gas generator. I have mixed mine, and used it, but feel the best way forward from here, is to get it out the house until such time it's gassed off enough to pour it away.

It's a shame we don't have someone that actually did chemistry here.

The stuff did come as prills. Little pieces of fairly uniform size, that other users count into their tanks. It's nasty to handle, but I might keep some about. Today my 70L tank took 0.25g which is manageable.

I would think it would work well. You get calcium ions and hypochlorous acid. When the free chlorine reacts with anything, or evaporates it leaves o2.

It may actually be a good way to boost calcium without nitrogen.

I used pool shock for years. I switched to southern ag garden friendly fungicide about 5 years ago and gave zero root issues in some pretty warm water.

 

[Ca++]

My concerns are it's stability, and it's instability making toxic gas. I can't put my finger on the numbers. I will be opening the bottle by the extractor, and not checking it for smell at that point. It's not on the shelf to buy, so I guess not possible to keep. The 2 months limit being all I found, but that's just an off-hand comment.

Pool hardness is increased with calcium chloride. Calcium oxide is cheap enough, but makes a very weak stock. Chalk (or Calcium Carbonate) is abundant in many peoples tap, and a good buffering solution, that RO users might look at.