Pool Water Analysis

[grollies]

OK, new pool, all seems well. Salt chlorinator working ok. Only trouble is I left the water analysis till last.

 

Water is sparkling, tiny bit of algae growth regularly brushed off and vacuum every 3 to 4 days.

 

Only checking pH at the moment with strip kit and seems about right.

 

I'm now looking for advice from you experts out there for a kit(s) that will monitor the following:

 

pH

chlorine (total & free)

alkilinity  (total & free)

calcium hardness

salinity

cyanuric acid

TDS

 

Are the above a minimum or a bit over the top?

 

Don't mind spending a few quid.

 

Pool approx 120m3 volume.

 

Your comments much appreciated.

 

grollies

 

[Crossy]

I use "PoolCheck 6in1" test strips which do everything you want except Salinity and TDS (there are additional PoolCheck products for each).

 

These:-

 

 

http://www.sensafe.com/pool-check/poolcheck-6in1/

 

I got mine from the States but I'm sure they will be available here.

 

If you're getting algae you need more chlorine (longer run time), have you used any stabiliser (CYA) at all? Without it your chlorine will burn off very rapidly.

 

 

 

 

 

[kamalabob2]

I recently was in Surin and I bought Aquachek 7 way test strips 100 test strips near the Elephant Stadium. That company, Thailand Pool Shop offered me fair prices on swimming pool chemicals I could not see on the shelf in Buriram. Richard indicated he sent swimming pool test strips and any swimming pool chemicals to all provinces in Thailand via a transport company. The Aquacheck test strips are simple to use for my family in Buriram Province.  

[Crossy]

1,195 Baht (plus shipping) for 100 tests.

 

http://thailandpoolshop.com/shop/water-testers/aquachek-7-test-strips/

 

 

[grollies]

12 hours ago, Crossy said:

I use "PoolCheck 6in1" test strips which do everything you want except Salinity and TDS (there are additional PoolCheck products for each).

 

These:-

 

 

http://www.sensafe.com/pool-check/poolcheck-6in1/

 

I got mine from the States but I'm sure they will be available here.

 

If you're getting algae you need more chlorine (longer run time), have you used any stabiliser (CYA) at all? Without it your chlorine will burn off very rapidly.

 

 

 

 

 

Cheers, increased salinity and algae gone. Lothe to add more chemicals to keep TDS down. Pool 95% covered by roof and pump & chlorinator runs 8 hours during daylight.

 

Test strips ok but as I'm a bit 'teccy' looking for digital analysis rather than test strips.

 

 

[SantiSuk]

What is free alkalinity? I, like many, test for total alkalinity but have never heard of free alkalinity. Whatever it is you can probably cut that one out .... unless someone else comes on here with a convincing case.

 

Personally I don't like test strips. The colour matching is very rough and ready and they 'go off' quite quickly if you happen to get an old batch from (an online) supplier IME. ie they can give false readings - you might want to test your strips first when you purchase - and 6 months later by comparing a pool reading with a pool reading diluted by half with ideally distilled water (but bottled water ok).

 

I prefer to use a digital read-out machine ('Scuba' - German made) for TCL, FCL, pH and CyA and colour-changing tablets for TA and calcium hardness. More expensive (the reader is about 6,000 baht) and I have to self-import, but removes any doubt. I do use the cheap dropper kits for more regular pH and CL testing. I find that the pH dropper/tube is the only cheap test where you can be reasonably confident of matching the result - I find detecting the difference between 1.5 and 2.5 on a CL tube very difficult to distinguish. 

[Anthony5]

16 hours ago, grollies said:

Cheers, increased salinity and algae gone. Lothe to add more chemicals to keep TDS down. Pool 95% covered by roof and pump & chlorinator runs 8 hours during daylight.

 

Test strips ok but as I'm a bit 'teccy' looking for digital analysis rather than test strips.

 

 

 

How are you supposed to get TDS down by adding more chemicals?

 

The 7 in 1 test strips from Thailand pool shop, as linked by Crossy, are a fair price but ask for the expiry date which is printed on the bottle.

 

You better run half of those 8 hours after sun has gone down, because the chlorine generated during that time will stay active all night.

 

Anyway, depending on your pump and filter capacity, I think 8 hours is overkill. I have a 60 cubic SWG pool which isn't covered and I run pumps for 2 x 2.5 hours a day, and during dry season 2 x 2 hours, for a perfectly healthy pool

[grollies]

9 hours ago, SantiSuk said:

What is free alkalinity? I, like many, test for total alkalinity but have never heard of free alkalinity. Whatever it is you can probably cut that one out .... unless someone else comes on here with a convincing case.

 

Personally I don't like test strips. The colour matching is very rough and ready and they 'go off' quite quickly if you happen to get an old batch from (an online) supplier IME. ie they can give false readings - you might want to test your strips first when you purchase - and 6 months later by comparing a pool reading with a pool reading diluted by half with ideally distilled water (but bottled water ok).

 

I prefer to use a digital read-out machine ('Scuba' - German made) for TCL, FCL, pH and CyA and colour-changing tablets for TA and calcium hardness. More expensive (the reader is about 6,000 baht) and I have to self-import, but removes any doubt. I do use the cheap dropper kits for more regular pH and CL testing. I find that the pH dropper/tube is the only cheap test where you can be reasonably confident of matching the result - I find detecting the difference between 1.5 and 2.5 on a CL tube very difficult to distinguish. 

OK, sorry, meant TA.

 

I'm not keen on test strips as I too find them difficult to interpret.

 

I'll look up Scuba but have since found the Hanna test instruments online - not cheap

 

Thanks for the info, grollies

[grollies]

9 hours ago, Anthony5 said:

 

How are you supposed to get TDS down by adding more chemicals?

 

The 7 in 1 test strips from Thailand pool shop, as linked by Crossy, are a fair price but ask for the expiry date which is printed on the bottle.

 

You better run half of those 8 hours after sun has gone down, because the chlorine generated during that time will stay active all night.

 

Anyway, depending on your pump and filter capacity, I think 8 hours is overkill. I have a 60 cubic SWG pool which isn't covered and I run pumps for 2 x 2.5 hours a day, and during dry season 2 x 2 hours, for a perfectly healthy pool

You won't get TDS down by adding more chemicals. I've had the pool going for 2 months and only put in salt.

 

I was replying to Crossy in that I don't want to start adding cyanuric acid (or anything else for that matter) if I don't need to as I'm on borehole water, hard with a fairly high TDS already.

 

noted on the run timing for the pump during the night, runs 0500 to 0700, four hours  during the day and 1600 to 1800 at present. Like I said, the pool is 95% shaded so degradation of chlorine shouldn't be an issue due to sunlight exposure?

 

Regarding T/O of pool depends, what is your pump capacity on 60m3 pool volume?

 

Appreciate the comments gents, cheers grollies

 

 

Edited October 22, 2016 by grollies

[SantiSuk]

If you want some free calcium test tablets PM me for my address and send me a stamped addressed envelope Grollies. I bought  a bottle with one hundred tabs earlier this year and I won't use a quarter of those before they go out of condition in a couple of years time - you really only need to test every 3 or 6 months IMO and I've laready established that I am nowhere near having a calcium issue (even though my well water TDS is very high for some non-calcium reason.

 

You keep adding tablets  to 50ml of pool water until the colour very obviously turns deep violet.

 

PS salinity meters are expensive but you can buy cheap TDS meters (outside Thailand!). If you have one source of water for your pool then you can get to salinity levels by deducting source water reading from salted pool water reading.

 

[Can't be so generous with my TA tablets unfortunately. I get through 100 in two years no bother as my TA bounces around a lot during seasonal changes - tends to drift down in dry season and plummets in wet season - its a function of markedly different TAs of my underlying 3 source waters (well, village and rain - the latter can have a TA as low as 20! - acid rain and all that)]

Edited October 22, 2016 by SantiSuk

[Anthony5]

28 minutes ago, grollies said:

You won't get TDS down by adding more chemicals. I've had the pool going for 2 months and only put in salt.

 

I was replying to Crossy in that I don't want to start adding cyanuric acid (or anything else for that matter) if I don't need to as I'm on borehole water, hard with a fairly high TDS already.

 

noted on the run timing for the pump during the night, runs 0500 to 0700, four hours  during the day and 1600 to 1800 at present. Like I said, the pool is 95% shaded so degradation of chlorine shouldn't be an issue due to sunlight exposure?

 

Regarding T/O of pool depends, what is your pump capacity on 60m3 pool volume?

 

Appreciate the comments gents, cheers grollies

 

 

 

 

I have a 1.5Hp Hayward super II pump, which is rated at 115 GPM and a 30" Hayward Pro sand filter whgich is rated at 98 GPM, but I suspect has a higher flow rate as I have filled with Zeolite instead.

 

Between 1 and 2 time turnover in 24 hours should be sufficient. If I recall correct I'm supposed to get 1.5 time turnover and I have a very clear pool, with the only thing I add is pool salt, and may be twice a year TCCA chlorine to increase the CYA. My CYA levels are around 50ppm.

 

I haven't added HCI for more than a year, since my water supply is low pH well water, and I have a digital pH meter so I know the level is correct. I keep between 7.0 and 7.5

 

 

My chlorinator has a pH module, but it has been disconnected long time already .

[sappersrest]

On 10/22/2016 at 8:48 PM, Anthony5 said:

 

 

I have a 1.5Hp Hayward super II pump, which is rated at 115 GPM and a 30" Hayward Pro sand filter whgich is rated at 98 GPM, but I suspect has a higher flow rate as I have filled with Zeolite instead.

 

.

Remember these are max flows that the pump manufacturer makes at a certain head pressure usually indicated on the data plate, to get a realistic idea of pump flow you will need , a pressure gauge to be fitted on the discharge pipe or some manufacturers actually have a tapping on the pump itself, this complete with the manufactures pump curve data will give a good indication of the pumps performance.  

The rating of the filter is the same, the max flow through the filter .With the absence of the flow meter in the system, and given the rated figures you have provided if the system were to run as stated  your filtration rate is around 48m3 per m2 of filter which is at the very top end of an acceptable filtration rate, at these rates the filtration is not that efficient probably filtering out only 10% of turbidity particles in one pass.

Also with good engineering practice the flow velocity through a 2 inch pipe at 2m/second will give you a flow of  around 15 m3/hr.

 

Working on the basis of conversion of US galls to litres.

 

So really it aint all about whats printed on the label.

[sappersrest]

After using water testing kits for the past 30 years my recommendations are.

 

Pool testing equipment

,http://www.sensafe.com/pool-check/poolcheck-6in1/ a very good product made by a reputible company

http://thailandpoolshop.com/shop/water-testers/aquachek-7-test-strips/ these are made by a company called Hach probable the best in the world, fantastic strips that i have tested against a bench photometer always come out accurate.

http://www.lovibond.com/en/pool/rapid-tests/scuball A good bit of kit in the lower end of the photometer market reasonably accurate for home pool use.

http://www.lovibond.com/en/pool/photometer/md-100 A good entry level kit for home user and small hotel

http://www.lovibond.com/en/pool/photometer/md-200 a very good bit of kit of all aspects of pool chemistry

http://www.lovibond.com/en/pool/comparator/comparator-2000 An extremely good comparator  excellent for home use ph and Cl only though

http://www.palintest.com/en/products/pooltest-3-photometer A bloody fantastic bit of kit can't say any more

http://www.palintest.com/en/products/pooltest-9  The best   used one for years

http://www.palintest.com/en/products/pooltest-9 The finest money can buy

 

http://www.sensafe.com/photometers/exact-micro-10-2/ A really good bit of kit  BEST BUY IMO

 

http://www.sensafe.com/accessories/kits/exact-micro-20-well-driller-kit/ All the above plus more especially for those who have wells, this is the one I use along with the palin kit

 

The lovibond  bond website is worth a browse

 

There are others on the market Hannah instruments spring to mind an sold by the forum sponsors from what i have herd very good bits of kit and the company has been around for many years, they make very good calibratable  TDS meters

 

So if I had a garden pool what would I use,  in order of preferece

http://thailandpoolshop.com/shop/water-testers/aquachek-7-test-strips/

,http://www.sensafe.com/pool-check/poolcheck-6in1/

http://www.sensafe.com/photometers/exact-micro-10-2/

http://www.lovibond.com/en/pool/rapid-tests/scuball

I

f cost did not mater, but to me it would seem like work

http://www.palintest.com/en/products/pooltest-9 The finest money can buy

 

PS I dont have a pool.

[sappersrest]

A good little hand book worth printing off.

lovibond_handbook_gb.pdf

[Anthony5]

On 10/26/2016 at 3:00 PM, sappersrest said:

Remember these are max flows that the pump manufacturer makes at a certain head pressure usually indicated on the data plate, to get a realistic idea of pump flow you will need , a pressure gauge to be fitted on the discharge pipe or some manufacturers actually have a tapping on the pump itself, this complete with the manufactures pump curve data will give a good indication of the pumps performance.  

The rating of the filter is the same, the max flow through the filter .With the absence of the flow meter in the system, and given the rated figures you have provided if the system were to run as stated  your filtration rate is around 48m3 per m2 of filter which is at the very top end of an acceptable filtration rate, at these rates the filtration is not that efficient probably filtering out only 10% of turbidity particles in one pass.

Also with good engineering practice the flow velocity through a 2 inch pipe at 2m/second will give you a flow of  around 15 m3/hr.

 

Working on the basis of conversion of US galls to litres.

 

So really it aint all about whats printed on the label.

 

I don't dispute your comments, as they are perfectly correct theoretically but 5 years of trouble free pool, without algae or other infections and a real minimum in chemicals needed, show that my maintenance procedures work in real life.

[sappersrest]

Sorry it was not meant to be personal ,I am sure from what you have previously posted your pool is in fact in tip top condition.

It was really meant to point out to other readers of this forum you don't always get what you think you have.

I would realistically think that you are probably in fact getting a flow of around 25m/3 max per hour.Especially as your pool is looking good.

Regards

[Rhys]

I wish a certanin university pool had a better way to test for water quality... Green no swimming.. Not green go for it.. SAD..

 

[SantiSuk]

Was at a resort (ie hotel with little villas) in Hua Hin last week and the pool was advertising its pH and CL checks. pH was fine but CL was proudly advertised by the maintenance contractor as 1.0.

 

Might have swum in it myself (with ear plugs) on a quiet day, but surely not sanitary enough if it happens to have a load of bathers? Probably only Total Chlorine - who knows what Free Chlorine might have been. [It actually looked cleaner and more inviting than most pools have to say]. 

[grollies]

Thanks to all for the replies and offers of help. Sappersrest great info. Haven't had chance to reply until now due to unscheduled backhoe track drive failure and repair