Faster Dissolving Cyanuric Acid

[chem geek]

I was told that Hasa makes a Cyanuric Acid that is a baby fine powder so dissolves in a bucket reasonably well and is shown here? Most CYA takes a while to dissolve so their pulverizing it into a fine powder will certainly help. Has anyone tried this? Does it dissolve more quickly? I used Dichlor this season to raise the CYA somewhat, but was not happy with it's somewhat incomplete dissolving (had to mix with water several times) and it seemed to have some residue that made the water taste more metallic for a few days (no, I don't drink my pool water, but do taste it when swimming).

There is also a liquid slurry form of conditioner called Instant Pool Water Conditioner shown here, but that's about twice as expensive (or more) as regular CYA. I spoke to the chemist who created this -- it's a slurry of the monosodium salt of cyanuric acid so is close to pH neutral and mixes instantly with pool water.

Richard

 

[duraleigh]

Richard,

I have found HASA initially tough to deal with but, since I am now a dealer, they have become more responsive. I will discuss this product with them and report my impressions ASAP....it sounds very interesting.

I would entertain selling their products on my site but I am concerned about the shipping costs...both from them to me and them me out to everyone. I'll respond more on Monday.

 

[Guest]

According to the Hasa website they recommend pouring it in the skimmer or making it into a SLURRY and adding it directly to the pool, pretty much standard ways to add CYA. There is NO mention of this being a fine granular product or being fast dissolving. There is a big difference between the product dissolving in the water a dispersing in the water. CYA is slow dissolving. Pool owner patience is needed. While I am at it WHERE IN THE WORLD DID ALL THIS 'PUT THE CYA IN A SOCK AND IT WILL DISSOLVE FASTER' come about? IT IS SIMPLY NOT TRUE and it's getting repeated over and over again too many times for my liking in this forum and a few others. Remember, this is EXACTLY how the 'slug acid to lower TA' myth got started! Pouring it in the skimmer (or making a slurry if you don't have a skimmer) is the accepted way to add CYA. IF you run your pump 24//7 a good part of it will be dissolved within about 48 hours. It's still a good idea to wait a week before cleaning your filter since I have seen the level creep up just a bit more during that week in a lot of pools.

Interestingly Hasa also sells anhydrous ammonia to produce monochloramine to kill algae! THAT partiular treatment is rarely used anymore. Ammonium Chloride and quaternaries are usually used instead in such products as Yellow Treat. In any care it's a cure worse than the disease.

 

[duraleigh]

While I am at it WHERE IN THE WORLD DID ALL THIS 'PUT THE CYA IN A SOCK AND IT WILL DISSOLVE FASTER' come about? IT IS SIMPLY NOT TRUE and it's getting repeated over and over again too many times for my liking.

I can tell you it got started over at PF as a way to still add CYA but give you the option to backwash. Now that makes sense and, if your clearing a green pool, is very applicable. But, I agree, it's almost getting mentioned as the de facto way to introduce CYA. It should be used only if you think you'll have the need to backwash.

 

[Guest]

While I am at it WHERE IN THE WORLD DID ALL THIS 'PUT THE CYA IN A SOCK AND IT WILL DISSOLVE FASTER' come about? IT IS SIMPLY NOT TRUE and it's getting repeated over and over again too many times for my liking.

I can tell you it got started over at PF as a way to still add CYA but give you the option to backwash. Now that makes sense and, if your clearing a green pool, is very applicable. But, I agree, it's almost getting mentioned as the de facto way to introduce CYA. It should be used only if you think you'll have the need to backwash.

This is true if the CYA stays in the sock. It is still going to take a week for it to dissolve and you are still going to lose some of it to backwashing (you have to add water to make up for what you backwashed out and that will dilute the CYA). I feel very strongly that this needs to get nipped in the bud! It's just wrong!

 

[Aquaman95]

Powdered CYA is actually quite common industrially. That's all I use in my pool. It comes in 55 kg bags. It does dissolve a bit quicker.

 

[mas985]

While I am at it WHERE IN THE WORLD DID ALL THIS 'PUT THE CYA IN A SOCK AND IT WILL DISSOLVE FASTER' come about?.

I think it is because that it "appears" to dissolve faster but this can be deceiving. In the past, I have used a skimmer sock filled with CYA in a leaf rake and I can get the CYA to dissolve enough to pass through the skimmer sock within a few hours by squeezing the sock. However, I have found that this method and probably the other sock method simply reduces the size of the CYA particles so they pass through the skimmer sock. Even by reducing the size of the particles, it seems as though it still takes about a week for the CYA level in the pool to rise where I can measure it.

 

[duraleigh]

Well, since this thread is completely hi-jacked, let's continue. I believe the CYA in a sock has a place. If you are clearing a pool and backwashing frequently, you will lose virtyually all of your CYA on the first backwash if you put it thru the skimmer. Placed in a sock, you will likely retain in excess of 90% of the CYA in your pool.....it's not cheap.

So, while it is not the preferred method, I think it has a very valid place when the need to get CYA in the pool and the need to backwash conflict.

 

[Guest]

If you are clearing a pool and backwashing frequently, you will lose virtyually all of your CYA on the first backwash if you put it thru the skimmer. Placed in a sock, you will likely retain in excess of 90% of the CYA in your pool

I disagree, I believe you will lose a LOT more than 10%.

 

[Guest]

Well, since this thread is completely hi-jacked, let's continue.

Why is this thread hijacked??? :?: It is a discussion on "faster dissolving" CYA (and doesn't specify whether this is by method of dissolving or physical characteristics of the chemical) and I contend that there is no such animal (exlcluding the liquid stuff which, technically, is NOT CYA but a salt of CYA) and that the often touted 'method' to make CYA dissolve faster by putting it in a sock is a myth. You have even said as much and said the sock is not to make it dissolve faster but to help prevent wholesale loss if you need to clean the filter before it is dissolved. It will to an extent but, as you have stated, this is for the specific instance where there is a need to add CYA while killing algae, which is a very specific case.

If you are clearing a pool and backwashing frequently, you will lose virtyually all of your CYA on the first backwash if you put it thru the skimmer. Placed in a sock, you will likely retain in excess of 90% of the CYA in your pool

I disagree, I believe you will lose a LOT more than 10%.

 

[chem geek]

Assuming one waits a week before backwashing, is putting CYA slowly into the skimmer to get caught in the filter something that is appropriate for all filter types -- sand, DE, cartridge? I can understand why it takes a while for the CYA to dissolve when caught in a filter because the flow rate through the filter media is rather slow, especially for an oversized cartridge filter such as what I have. The GPM is spread out over a rather large surface area. I would expect faster flow rates to make the CYA dissolve faster -- up to a point.

This patent describes how to make the monosodium salt of CYA by slowly adding sodium hydroxide (lye) to a slurry of Cyanuric Acid over a period of around 40 minutes, but requires very fine CYA particles to start with. This is not exactly the same method used to make the liquid conditioner product, but the resulting compound is the same. DO NOT TRY AND DO THIS -- I just thought it was interesting.

Richard

 

[sredish]

whats the prob with powdered cya sprinkled around the pool?

 

[duraleigh]

whats the prob with powdered cya sprinkled around the pool?

It's pretty acidic. In a plaster pool, it may not do much harm, but, because it dissolves so slowly, it's not something you'd want touching a vinyl liner. I don't think I'd want it touching my plaster either....just to be safe

 

[mas985]

I think there is now some evidence that CYA will etch a plaster pool if left on the surface or even if CYA is maintained at a very high level, so I would not sprinkle it around and let it sit on the surface.

 

[chem geek]

If you're talking about this study, that has been brought into serious question. Others have tried to reproduce these results and have been unable to do so. It appears that the saturation index was not accounted for and furthermore no drop in CYA levels has been seen with others trying to reproduce this. So I don't consider this as absolute. Nevertheless, I agree that it is best to play it safe and not dump CYA directly into a pool.

 

[Guest]

Assuming one waits a week before backwashing, is putting CYA slowly into the skimmer to get caught in the filter something that is appropriate for all filter types -- sand, DE, cartridge?

IMHO, yes!

I can understand why it takes a while for the CYA to dissolve when caught in a filter because the flow rate through the filter media is rather slow, especially for an oversized cartridge filter such as what I have. The GPM is spread out over a rather large surface area.
So would the CYA so the concentration of it in any one area would be much lower than in a smaller filter so it would probably be close to a break even.
I would expect faster flow rates to make the CYA dissolve faster -- up to a point.


Richard

 

[Ohm_Boy]

Well, for my half-cent, I don't believe any sock will have an effect on the rate of dissolve. I do believe that it will keep one from vacuuming up the CYA while cleaning the pool, and it may keep some of the cya powder out of the filter so that it won't be lost to a backwash, but the powder disolves at the same rate whether it's in a sock or not.

 

[sredish]

the sock isn't to make it dissolve faster, it's plainly just to hold it and in most cases in an area of flow so that it can dissolve safely, off the floor of the pool and not in the filter...

 

[Guest]

IF you are just trying to raise your CYA and don't have an algae bloom the easiest way is to just clean your filter, pour the CYA in the skimnmer, run the pump for 24-48 hours, and don't clean the filter for a week. Why make more work?

 

[JasonLion]

The most significant case where there is a problem is fighting algae with a DE filter. DE filters can require frequent backwashing when fighting algae. If you are also trying to raise the CYA level at the same time there is a problem.

It isn't clear to me that CYA which vanishes from a sock has really dissolved. The "vanished" CYA may end up in the filter anyway. But if you need to backwash isn't trying the sock approach better than knowing you will lose what you put in the filter?