chlor galet pool

[osie]

Hi All

I am using gallets in the pool which is new to me... It all seems to be working fine but I would like to ask if there is a specified amount of time that the water needs to circulate in the pool(using the filter).

I used to use a salt cholorinator which meant : temperature of water / 2 = number of hours to run the pump.

Another question is : which galets are recommended to buy.  I think they have a specification based on 1 galet = n metres  water for n days.  Is it just a case of chosing the one that costs less for the amount of water / time is works.  The prices seem to vary between 20euros / 5 kg  or 20euros / 10kg.

Thanks

osie

[The Ps]

The same principle applies for timing of the pump operation.    For example, water at 26 degrees = 13 hours.

Chosing galets is nothing to do with timing, only water volume.   There are a huge variaty on the market and as you say, the costs vary.   Some of the cheaper brands contain fillers and this is sometimes reflected in the volume they will sanitise and how many days they will last.   If you are using galets then choose one with a stabiliser in it (cyanuric acid) especially in areas where there is high UV exposure.

Andrew may qualify but I am not sure on how you would get on with zealite filters and using multi action galets containing flocculants.

You can buy galets also specifically for liner pools.

 

[Poolguy]

Osie

Thanks for the question.

I recommend that circulation time is based on the capacity of your pump and filter/volume in the Pool.

I mean by that - you should filter ALL the water in the pool twice per day. That means that the whole volume of your pool should pass through the filter at least 2 times in a day.  These are the same recommendations from the Department of health for 'public pools'. As your pool is for public use you should pay attention to this directive.

 Another example

Calculating the circulation time (CT) is the debit (capacity) of the pump - say 22meters3:hour divided by the pool volume say 75m3 that would make 3.4 hours (CT) X 2 = 7 hours.

Now if you CT is 5 hours then that would mean that the pump should run for 10 hours.

In my opinion is really nothing to do with temperature (greatest respect to my Colleague) as everyone’s pool has not the same ratio of equipment to volume.

How much chlorine to dose is a matter of testing to see the correct levels which will vary depending on: bather load, temperature of the water, exposure sunlight; concentration of stabiliser, filtration rate, oxygen content of the water, covered or not, season of the year, level of contaminants, distance of the filter to the pool, type of filtration, 'freshness' of the chlorine, pH, total alkalinity, and a few other minor issues. So test with a good photometric tester (I recommend Scuba+) and dose accordingly, then test again in a few days later to check.

If you choose Zeolite in your filter then do not use any product with Flocculent. There are é reasons, you already have the best filtration on the market so you do not need a plasiticiser (floc) in the water to help and second it will block the pours of the Zeolite, which will limit the life of the product.

I hope that this has been of help

Andrew

 

[Jonzjob]

Even better than that Osie, you would be much better off is you had an auto chlor/PH doser. We have had one for over 2 years now and I would recomend it to anyone. It takes the guess work out of what water quality you are swimming in, especially if you have zeolite in your filter too. It is a fair bit more expensive than gallettes, but what price is your health worth, in my humble opinion that is?? You then use liquid chlor (javel) and sulphuric acid for the PH. Don't balk at the acid thing because as long as you respect it then it is perfectly safe. The liquids are a lot less expensive than the gallettes and the system is far more accurate than the guesstamating of gallettes!

Andrew may well be able to give you the details on that me thinks?

[osie]

The auto option would of course be the best however the price is out of the budget... at least for this year.

The mathematics from Andrew(Thanks!!) are great and I now need to figure out the variables.

As for which gallet.. it looks like you need to read what concentrate you get for your money and then get the best one.

Thanks

osie

[Jonzjob]

When you are using the slow release gallettes it's a good idea to keep an eye on the cyanuric acid (stabiliser) level as well because it will build up over time and eventually stop the chlor from working. Your best level is about 50 ppm if my memory serves me correct. Andrew will correct ct me if I'm wrong [:D]

[The Ps]

Cyanuric acid - 30 to 150 ppm is the window.

[Poolguy]

I prefer 30-50ppm range.

 

After that the molicule is too heavy and cannat act causeing 'Chlor lock'

Very important to keep a check on it with an accurate tester.

 

Andrew

[The Ps]

What has changed since the support you give for  the information on the link http://piscinesforum.com/forum3/showthread.php?p=38 where it states 'CYANURIC ACID Also called condition and stabilizer - Chemically, conditioner is cyanuric acid. It protects chlorine in the water from being destroyed by sunlight. Minimum level is 10 ppm. Too much does not slow down chlorine activity or effectiveness. Does not protect bromine from sunlight.'

30 - 150 is the guide.   I woud prefer 30 - 50.   In fact I would prefer bang on 30 but it rarely happens and that is why there are published safe ranges.

In reality we are dealing with a whole host of things with too many variables to make everything completely accurate.   The closest you will get to that is by using the Langelier Saturation Index but even when that has been set on a pool, then next day it may have changed.

This is also from the same site and as a top line guide it is fine - 'Run your pools filtration for at least 12 hours a day, most of the time you should take the temperature of the water and half it to give you running hours, e.g 24 degrees C = 12hours a day. stick to that for starters.'  

Again there are variables, some of which you refer to but don't leave poeple with the impression that what I have said is wrong.   Neither of us are wrong.   There are several pool experts out there (some better than others) and you can google to your hearts content and find several preferences recemmended by people in whose opinion set themselves up as right but it is just their opinion.   As long as this is within the guidelines recommended then there is no issue.   Only wildly  false reporting and contraditions should be challenged.

If people want depth and detail, it is extremely hard in some cases because you don't get the full picture without visiting a pool.   I am merely trying to help when and where I can as a qualified professional and with my opinions on a black and white situation.   Even the Langelier Saturation index is not the best guide but offers an opinion on certain parameters adapted for pools from a system originally designed for closed water systems.   It is the most robust guide so far though.

Pleae don't read this as an attack on you or your knowledge.   You are clearly well qualified and offer a great service to people.  All I am asking for is consideration for the way I answer sometimes given my time restraints and for any follow up comments to be fair -  and by all means, if I am wrong, challenge it.   Tehcnology moves on, things change and we all come up against new learning opportunities and I am happy to learn from fellow professional as well.

 

[Poolguy]

Quite right John   ....Point well made.

We are both trying to help.

I too do not want to contradict you, but wish to add my preference.

Andrew