Translate to:

Information

Water Chemistry

This group is for in-depth discussion of pool and spa water chemistry issues at a more technical level suitable to a group for those who are interested.  The emphasis is on matching science and research to real-world observations.

Members: 74
Latest Activity: Apr 15

Discussion Forum

Cyanuric Acid for Indoor Pools? 3 Replies

Started by Howard J Knight. Last reply by Jory Jan 19, 2017.

flocculant 8 Replies

Started by Frank H Dashti. Last reply by Roohollah Akbari Jun 21, 2016.

Phosphates, Phosphate Removers and CuLator™ Metal Remover 57 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Apr 24, 2013.

Combined Chlorine-what is it exactly? 6 Replies

Started by David Rockwell. Last reply by Richard A. Falk Dec 29, 2012.

The mysterious case of the disappearing CYA 7 Replies

Started by David Rockwell. Last reply by Rick Larson Oct 10, 2012.

Natural Swimming Pools (NSPs) 1 Reply

Started by Richard A. Falk. Last reply by John Pustai Jul 27, 2012.

Enzymes 18 Replies

Started by Richard A. Falk. Last reply by Aaron Heiss Jul 5, 2012.

Oxidation-Reduction Potential (ORP) 6 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Jun 11, 2012.

Breakpoint Chlorination 4 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk May 29, 2012.

CYA, TA, and the Langelier Index 1 Reply

Started by David Rockwell. Last reply by Richard A. Falk Feb 12, 2012.

SWG and borates 5 Replies

Started by Jeremy Hine. Last reply by Richard A. Falk Dec 4, 2011.

Air Quality Above Pool/Spa Water 3 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Nov 17, 2011.

Biofilms 28 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Jul 12, 2011.

Algae 3 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Jun 9, 2011.

Chlorine Dioxide 2 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Apr 8, 2011.

Total Dissolved Solids (TDS) 6 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Mar 19, 2011.

Active Chlorine Level and Disinfection By-Products (DBPs) 14 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Mar 10, 2011.

Lowering Total Alkalinity (TA) 5 Replies

Started by Richard A. Falk. Last reply by Richard A. Falk Feb 23, 2011.

Total Alkalinity (TA) and pH Effects 1 Reply

Started by Richard A. Falk. Last reply by Richard A. Falk Feb 21, 2011.

Comment Wall

Comment

You need to be a member of Water Chemistry to add comments!

Comment by Richard A. Falk on April 4, 2011 at 7:38pm
Ann, can you please be more specific about how the water samples submitted to your laboratory are failing?  Are you talking about bacteriological testing, disinfection by-products (chloramines, THMs, etc.) or something else?  When you say they seem to be doing everything right, do you mean water chemistry parameters are within code limits?
Comment by Kevin Woodhurst on April 4, 2011 at 6:58am
What a great group and discussions... Thanks Richard...
Comment by Ann Klute on April 4, 2011 at 6:48am
Thank you for this discussion.  We have had people continually fail water samples submitted to our laboratory.  Since we also inspect the pools and spas we tried to figure out what could be the problem.  They seemed to be doing everything right and yet continued to fail their samples.  I will forward on the information to their CPO and keep this info handy for our newsletter.  Looking forward to more great info.  Thank you.
Comment by Richard A. Falk on April 4, 2011 at 12:32am

I've added a discussion topic on enzymes as a placeholder for now, but will have to get back to it to fill in more info.

 

Some enzymes are more delicate than others.  Many of the ones used in pools will last up to a week, though it really depends on the enzyme and the chlorine level so will vary by product/manufacturer.  Enzymes should last a lot longer in pools with CYA than in pools without CYA due to the differing active chlorine levels though exposure to UV is another factor that might shorten enzyme effectiveness.

 

DBPs can cause respiratory and ocular irritation and potentially increase long-term cancer risk so in that sense they can be RWIs though usually that term is reserved for pathogens (bacteria, viruses, protozoa, etc), not chemicals.  Would way out-of-balance pH that irritated the eyes be an RWI according to him?  Consider the source of information -- this teacher isn't always accurate.

Comment by David Rockwell on April 3, 2011 at 11:03pm
BTW, the teacher classified DPBs as an RWI. Technically they could be considered a source of RWIs...I guess.
Comment by David Rockwell on April 3, 2011 at 10:59pm

Are we ready for a thread on enzymes?

My question is that I have always envisioned that enzymes are relatively "delicate" in that they are easily destroyed or their effectiveness reduced in the presence of a strong oxidizer like ozone, high chlorine as in shocking the pool, or even high temperature as in a spa. In view of that it would seem that they would be better used as a preventive measure as opposed to a corective one. I'd like to repost a link that Al gave us regarding "designer oxidizers" like Truox. http://ppoa.org/?p=282. (Hope that worked). If a service guy comes up on a green pool, keeping the chlorine low enough to allow the enzymes to work seems counterproductive. Or are enzymes not as fragile as I imagine?

 

Comment by Al Neumann on April 3, 2011 at 8:31pm

Thanks Richard. I was thinking DPB's, but put down RWI's instead. I was also referring to the clarifier and/or the PRS System product, which encapsulates the oil in a chlorinated environment.

I have a tendency to agree with you that all in all, when all is said and done, that the enzymes would end up having more of a beneficial effect, as that is what I have seen when we do end up using them.

It's just that David's and your comments got me to thinking...you know how that is.

Thanks again.

Comment by Lester Eric Brehm on April 3, 2011 at 8:28pm
Richard, I really appreciate your input especially because you have no other motive but to find the facts and not to sell a product. Also because your not funded buy by  a major chemical manufacturer.
Comment by Richard A. Falk on April 3, 2011 at 8:05pm

SeaKlear Natural Clarifier™ is made from chitosan, but their Enzyme Klear product is most certainly not chitosan.  Chitosan is a polysacchride and though it does have an amine group, it probably reacts slowly with chlorine, similar to urea.  So the clarifier is likely to sweep up particles, get caught in the filter, and get backwashed before it results in any significantly noticeable chlorine demand.

 

As for enzymes, they vary in how quickly they break down but they all do break down when chlorine is present which is why you need to add more on a regular basis.  However, the quantity of enzyme added is relatively small.  Remember that they aren't consumed in the chemical reactions that they speed up so you don't need a large quantity to have a large effect.  So though they would create some chlorine demand and probably produce some disinfection by-products (DBPs, not recreational water illnesses, RWI), the amount would be much smaller compared to bather load and blown-in organics, perhaps even for a residential pool.  I know that when I used Orenda's CV-700 enzyme product I did not notice any change in chlorine demand.  In pools with lots of organic load, one would expect a lowering of chlorine demand since the enzymes should oxidize many of the organics using dissolved oxygen or water (hydrolysis).

Comment by Al Neumann on April 3, 2011 at 6:23pm

I guess I was the one that rebuked David in Luke’s post on enzymes. I thought I was being diplomatic, but maybe I came off too strong… if so, sorry David.

 

I agree with David’s statement that it’s nice to have a source of rational verification of how some things work, as there is often so much mis-information and myths that appear to be rampant in this industry of ours. Learning is a never ending process, as it has a tendency to bring into play more and more questions about the what if’s; or what about this; or I was taught this time and again, so how can you say that this is not so…

 

So in that same vane, lo and behold, a question popped into my head that I hadn’t thought of before when David mentioned that he went to a class on RWI’s, and the talk got into enzymes, and you mentioned that enzymes are proteins with many nitrogenous sites.

In a chlorinated pool, enzymes will generally get slowly oxidized by chlorine since they are composed of protein that has many nitrogenous sites (after all, it is composed of amino acids joined by peptide bonds and these have nitrogen).

So putting two and tow together I came up with these questions.

  • The question is whether or not the by-products of the inevitable enzyme degradation are considered as a potential source of harmful RWI’s?
  • Do they contribute to the organic loading and are they considered to be part of the chlorine demand in a pool?   
  • If the answer to both questions is yes, then do the benefits of using enzymes outweigh the negative effects?  I’m thinking they would still be more beneficial than not to clean up the wall tiles and filters, but wonder for continuous maintenance. Maybe Sea Klear’s chitosan based products may in fact be a better choice once the pool is cleaned up, but chitin being a natural product, may pose similar questions.

Any thoughts?

 

Members (74)

 
 
 

Sign in

E-mail

Password
 or Sign Up
By signing in, you agree to the amended Terms of Service and Privacy Policy.
Forgotten your password?

Events

Latest Activity

Norman Tyree is now a member of Pool Genius Network
2 hours ago
Kevin Misley replied to robinsenny's discussion Installing and Operating an Efficient Swimming Pool Pump
"I will agree on the first point that larger pumps will cost more operate. In the early 1980's,…"
7 hours ago
Profile IconBeau Martin and Roberta DiFranco joined Pool Genius Network
Thursday
Karl Toth is now a member of Pool Genius Network
Jul 12
robinsenny posted a discussion

Installing and Operating an Efficient Swimming Pool Pump

Hi,The larger the pump, the greater your pumping and maintenance costs. Therefore, you want to use…See More
Jul 12
robinsenny is now a member of Pool Genius Network
Jul 10
Heidi Dayne Hanson updated their profile
Jul 9
A-TEX Family Fun Center posted a status
Jul 8

© 2018   Created by PGN Admin.   Powered by

Badges  |  Report an Issue  |  Terms of Service

Offline

Live Video