Does anyone with a Baquacil pool use the "CDX" product?

[three4rd]

Hi,

A few years ago Baquacil came out with "CDX" - a liquid that is added directly to the skimmer following the oxidizer. It is reported to work really well with avoiding the white water mold problem that is common to biguanide pools. The chemical in the product is apparently polyether diol. It is also supposed to help maintain the oxidizer level. A friend of mine said he has been using it faithfully for the last few years and has had no water problems, so I just started using it as well. There used to be a product called "Assist" that worked great to get rid of water mold, but it was discontinued a few years ago.

 

[Patrick_B]

The short answer is that eventually, your friend, or you....will have troubles with Baqua. It's a matter of when instead of if. Not many here will encourage the use of these products, but of course it's your pool, so do as you wish. Personally, I'll never use anything but Chlorine and I know I won't have trouble. It's so easy, and so reliable, there simply isn't a reason for me to change. Given that, and the security of knowing my pool is safe and sanitary for swimmers I'd never risk trying anything so iffy and expensive.

 

[three4rd]

I have had trouble, as I've already mentioned - with white water mold. The key is to know how to fight it and prevent it. The additional cost is the least of my concerns. Hopefully with better knowledge that I've gained here and with better maintenance things will go ok.

 

[tim5055]

Well CDX contains (no % given in the MSDS)

Hydroxymethyl-5, 5-dimethylhydantoin

2,4-IMIDAZOLIDINEDIONE, 1,3-BIS(HYDROXYMETHYL)-5

DM HYDANTOIN

Water

Best I can figure with Google is that it is some formaldehyde products and water. I'm sure chem geek can shed light on the product.

But to answer your question, no I don't use it.

 

[chem geek]

CDX contains primarily DMH (5,5-dimethylhydantoin) which is the same chemical used in bromine tabs but without the bromine and chlorine attached to it. In some sense it's like CYA is to chlorine except that the bromine isn't as strongly bound to it. What the CDX mostly does is allow for a lower addition of hydrogen peroxide oxidizer, possibly by stabilizing it to slow it's breakdown/degradation especially in sunlight.

As described in this Baquacil "treating water mold" document, they list procedures for such treatment even for pools using CDX so the claim that CDX prevents white water mold may be a hope, dream, or exaggeration though many websites make the claim. I think what happens is that in pools without CDX, the hydrogen peroxide oxidizer gets used up more quickly so IF one is not properly maintaining that oxidizer level then white water mold has a greater chance of growing. The CDX just has the hydrogen peroxide last longer so that lack maintenance is less likely to result in too low an oxidizer level.

So the bottom line is that CDX isn't the cure -- proper maintenance of the hydrogen peroxide oxidizer level is what helps prevent white water mold. If you believe you are unable to regularly test and maintain the oxidizer level, then CDX will have it last longer but if you then rely on that as a crutch and test and adjust even less frequently, then you may still end up with problems.

 

[Leebo]

We tried using the CDX system several years ago once it first came out. We were quickly disappointed with the results and skipped the extra cost. The largest two items we found worked best when using Baquacil was using their Performance Algicide and adding the Oxidizer weekly rather than the monthly they suggest. Also make sure your Sanitizer levels NEVER drop below the 50ppm levels as suggested. Any Baquacil system works best when you are able to stay on top of ANY water issues. The more you can do to avoid any haze or cloudy water, the better it works. Once you start to get any issues however with your water, it's a major fight (and expense) to clear it up.

 

[three4rd]

I agree totally with adding the oxidizer weekly. Since doing that (I used to add monthly), I've had much fewer problems. The gold standard for treating white water mold is "Assist", but I don't think that's available anymore. I started using CDX a few weeks ago, so we'll see what happens. So far so good.

 

[graler]

We used the CDX. Still ran into problems. It seems like we would get back on the path to clear or what we thought was clear. A little green would show up and it was curtains from there. I am in the process of converting to chlorine now. I can't even swim in it yet and I am thrilled. My water has never been this clear. We even had a bit of Algae at the start of the conversion. It is gone now. Literally overnight.

 

[three4rd]

CDX contains primarily DMH (5,5-dimethylhydantoin) which is the same chemical used in bromine tabs but without the bromine and chlorine attached to it. In some sense it's like CYA is to chlorine except that the bromine isn't as strongly bound to it. What the CDX mostly does is allow for a lower addition of hydrogen peroxide oxidizer, possibly by stabilizing it to slow it's breakdown/degradation especially in sunlight.

As described in this Baquacil "treating water mold" document, they list procedures for such treatment even for pools using CDX so the claim that CDX prevents white water mold may be a hope, dream, or exaggeration though many websites make the claim. I think what happens is that in pools without CDX, the hydrogen peroxide oxidizer gets used up more quickly so IF one is not properly maintaining that oxidizer level then white water mold has a greater chance of growing. The CDX just has the hydrogen peroxide last longer so that lack maintenance is less likely to result in too low an oxidizer level.

So the bottom line is that CDX isn't the cure -- proper maintenance of the hydrogen peroxide oxidizer level is what helps prevent white water mold. If you believe you are unable to regularly test and maintain the oxidizer level, then CDX will have it last longer but if you then rely on that as a crutch and test and adjust even less frequently, then you may still end up with problems.

Chem Geek,

I re-read some of your response to my inquiries about white water mold and the use of CDX, etc. If, as you say, maintaining the hydro-peroxide levels is a key factor in preventing growth of water mold, then wouldn't the use of Softswim Oxysheen (which I recently inquired about) - since it is primarily an oxidizer - be a more effective way of preventing water mold than using CDX? My pool store is claiming that with the use of Oxysheen there is no further problem with mold, etc. I'm just trying to decide which would be better - continue with CDX or try the Oxysheen?

Here's another idea....I came across a few websites that suggest this product is the replacement for Softswim Assist - http://www.commercialaquaticsupplies.com/Aquafinesse MSDS Pool Puck 3-2009.pdf Based on what is in this product, would this be an effective prevention for mold?

Thanks for any advice,
Keith

 

[chem geek]

Hydrogen peroxide and MPS are both oxidizers, but that doesn't mean they both affect white water mold in the same way. They might, or they might not. I simply do not know.

From what I wrote earlier, the CDX may have the hydrogen peroxide last longer, but again that doesn't mean that MPS will prevent white water mold. I don't know if it does or not.