Guide for swimming pool chemicals in Thailand  

Links to contents:

Introduction & disclaimer
Algicides
Algicides with flocculant (clarifier)
Flocculant (clarifier)
Ionization
pH regulator
Alkalinity
Water hardness
Chlorine
Other chemicals (stain removers, disintectant cleaners)

Disclaimer: All swimming pools in Thailand are different, there are many factors affecting your water chemistry. This guide is provided 'as is' based on SwimmingPoolsThailand's 20-year experience with tropical pools, and recommendations for water disinfection made by various governments. We accept no responsibility for the use of this guide and do not guarantee the performance of the products listed.

TESTING: Test strips for pH are not perfectly accurate. Fine for small pools, but for the the best results, use digital meters, or simple titration test kits. See water testing.

All our own brand 'Kleer' products and our dry chemicals have instructions on the web pages and in English, French, German and Thai on the labels.
If you don't find your answer here, create an account and get a free PDF copy or view the fully searchable online version of our General Catalogue. It's packed with more tips and tricks for pool care. Don't hesitate to contact us through our contact form for more free advice in French, German, and Swedish.

In some areas especially Isan,  and Koh Tao, you can book a  visit from one of our pool technicians at a very reasonable fee. He will test your water professionally, check your systems, and send you a full report.

ALGICIDES
Green algae turns water light green. If untreated, the water will soon become a thick, dark green soup.  It is the most common form of algae and it's what you'll find when you return to Thailand after an absence of several weeks. It can happen very quickly, even overnight after a tropical storm but it is not difficult to treat. If left too long however, the most economical solution is to change the water and thoroughly clean the floor and walls and flush the plumbing. Generally the correct level of chlorine will prevent green algae, but if it recurs often, use regular dosing of GreenKleer or install an ionizer. Algicides will not remove the green colour; the dead algae must be removed with a floccuant to clarify the water. Some of our products are a combined algicide-flocculant. See GreenKleer, an economical and highly effective non-foaming algicide. Immediately kills green algae.  See also AquaKleer for pools with cartridge fikters and D.E. filters.
Mustard and Red Algae are a slime that sticks to the walls, steps, and ladders. They are more rare than most strains but quite difficult to treat. See VerdiKleer for Mustard algae and most  other strains..
Black Algae is quite common but difficult to destroy. It generally appears on grout that is not special grout for pools. It grows into the grout and corners of the pool. If left untreated for a long time, the pool should be emptied and the algae treated locally and thoroughly removed with a wire brush. In many cases, regrouting will be necessary. See AlgiKleer for black algae. It works best on its own - do not mix with other SPTpools or other brands of algicides.
Black Algaetrine is a commercial strength for high use, large and commercial pools. A unique, patented combination of algicides specially formulated to control black algae and other resistant strains.

ALGICIDES with FLOCCULANT (clarifier)
After using an algicide-floccuant, the powder that settles on the pool floor must be vacuumed to the waste setting on the filter valve followed by a good rinse of the filter. KristalKleerPLUS is a combined algicide-flocculant ideal for domestic and smaller pools up to around 60m3 (a typical 4 x 10m pool). For larger pools, use separate algicides and flocculants.

 Be sure to use AquaKleer algicide + clarifier for D.E. and cartridge filtration systems.

IONIZATION
Another effective alternative for killing algae is to install a ClearBlue mineral ionizer. Easily installed in less than 30 minutes and costing less than a year's supply of chemicals for a medium sized family pool, an ionizer relieves you of the guesswork and much of the tedious maintenance. They will also save up to 90% on chlorine. Entirely harmless and fully environmentally friendly, an ionizer does not inject any chemicals into the water. The silver, copper, and zinc ions released into the water are today's state-of-the-art solution for algae-free and correctly disinfected water.
UV systems are also an excellent alternative to sanitation by chlorine. They need additional plumbing, valves, and space, and should preferably be installed by a pool professional. They are nevertheless also reasonably priced. See our Emaux UV sanitisers.


FLOCCULANTS (clarifiers, the same products are sometimes marketed more expensively as 'brighteners')
Flocculants clarify the water. They cause microscopic suspended impurities to coagulate into larger particles and then settle to the bottom of the container (or be filtered out) more easily. They do not remove dissolved minerals such as salt, iron, manganese etc. They are available as powders and liquids. Clarifiers should be left to work over night. The pool floor should then be vacuumed followed by a backwash and rinse of the filter  If using after a treatment for algae, vacuum the pool to the waste setting on your filter valve.

KristalKleer liquid water clarifier. Excellent quality - super low price. Recomended for domestic pools. Safe to use. Not for use with cartridge or D.E. filtration  systems.
KristalKleer-PLUS liquid water clarifier + algicide is one ofd Thailand's best selling pool products. Not for use with cartridge or D.E. filtration  systems.


Flocculant (water clarifier) Granules is flaked aluminium sulphate. Often marketed at excessively high prices, it's the most economical of all water clarifiers. For clarifying cloudy or dirty water.
 Not suitable for use with cartridge or diatomacious earth filters. Safe to use. Not for use with cartridge or D.E. filtration  systems.
  For very rapidly clarifying cloudy, green, or very dirty water, use FlocculantPLUS premium water clarifier powder. Not suitable for use with cartridge or diatomacious earth filters. Safe to use. Not for use with cartridge or D.E. filtration  systems.
 NOTE: Some clarifiers should not be used with cartridge or D.E. filters. For D.E. and cartridge filters, use 
AquaKleer algicide + clarifier, it eliminates green algae and increases water clarity.

PH REGULATOR
In order for any kind of pool sanitation system to work, the water pH must be between 7.2 and 7.6. The pH level indicates the relative acidity or alkalinity of your pool water. pH is measured on a scale from 0 (strong acid) to 14 (strong alkaline) and pH neutral is 7. In pools, a slightly alkaline level between 7.2 & 7.6 is ideal because this range is the most comfortable to the human eye, provides optimum use of free chlorine and provides water that is not corrosive or scale forming.
If the pH is too high, add pH Minus (dry acid) 10g per day (per 1000-litres) until the pH has decreased to between 7.2 and 7.6.
If the pH is too low, add pH Plus (10g per day (per 1000-litres) until the pH has increased to between 7.2 and 7.6.
A simple test kit for pH is not expensive and will also test the chlorine level. Our  premium grade pH Minus is a granular pH reducer made in Germany. Much safer and easier to use and store than liquid Hydrochloric acid (Muriatic acid). Best for manual addition to pool water. 

To raise the pH, use pH Plus. No fumes, no storage problems. Supplied in plastic tub. Contains Sodium Carbonate (Na2CO3). Harmless if swallowed, it is also an ingredient in toothpaste and sherbet powder.



ALKALINITY
The level for Total Alkalinity (TA) should be between 80 and 140 parts per million (ppm). Total Alkalinity is a measure of water’s resistance to change in pH – TA is the amount of alkali (not to be confused with alkaline) in the form of bicarbonates, carbonates and hydroxides present in the pool water. TA affects and controls the pH.
Total Alkalinity (TA) represents the ability of the water to resist changes to the pH level. Ideal Alkalinity will prevent pH 'bounce' and avoid damage to tile grout and tile adhesive. Ideally TA should be between 80 and 120. Over 120 may cause cloudy water. Under 80 will cause the pH to bounce and will damage equipment.
Total alkalinity should only be lowered when it causes a significant rise in pH levels, or when it causes calcium scaling through CSI. To lower pH and total alkalinity, use a strong acid such as muriatic acid, sulfuric acid, or sodium bisulfate, all of which lower both pH and TA, but at different rates.
Sodium bicarbonate (baking soda, bicarbonate of soda, NaHCO3,) 500 gr will raise 40,000 liters of water 10 ppm. It will raise the total alkalinity without excessively raising the pH. Our 1 kg and 4 kg packs are available at a fraction of the price of purchasing tiny sachets of baking powder from the supermarket. Not to be confused with sodium carbonate (soda ash) pH raiser.

HARDNESS
The water hardness should be maintained at a minimum level of 200ppm. Calcium above 400ppm can cause scale to form and leave limescale deposit on the tiles and fixtures and fitting and cause corrosion. It can also damage technical equipment such as salt water chlorinator cells, and despite the moving parts and high velocity of the water, it can also  build up inside the pump. Water that is too soft (uncommon in Thailand) will leach calcium out the tile grout and eat the grout away.
An excessive amount of pool chemicals can cause your water to be cloudy. That includes: high pH, high alkalinity, high chlorine or other sanitizers, and high calcium hardness.
Prolonged untreated water will cause the tile adhesive to dissolve, leaving loose tiles. To reduce some of the water hardness, use a flocculant to rid the pool of free-floating calcium carbonate. Vacuum the walls and floors to remove calcium carbonate particles. Backwash or clean out your pump filter.
there are no chemical methods for reducing water hardness

. The only way to fully reduce water hardness is to drain some of the water and dilute the existing pool water with fresh water. This will not help if you are filling your pool with well water that is already hard, in which case you should consider the installation of an ion exchange water softening system. To increase water hardness use Calcium Chloride flakes. Use about 750 gr of calcium chloride per every 40,000 liters of water to raise the hardness by 10 ppm. 


CHLORINE PRODUCTS
See also our extensive Guide to Using Chlorine.
Our chlorine products are listed in their own category.  Chlorine is the most commonly used pool sanitiser. It is important to maintain the correct level of chlorine at 0.5 to 1.5 ppm.  For domestic pools, a simple test kit is not expensive and will also test the pH. Adding chlorine is best done at dusk to avoid the sun's UV rays, and to allow the chlorine to work over night.



Nissan 90% TCCA stabilised chlorine GRANULAR. Very high quality. Available in 50 Kg and 20 Kg drums.



Nissan 90% TCCA stabilised Chlorine POWDER. Very high quality. Available in 50 Kg and 20 Kg drums. 

Nissan Hi-Lite 90% TCCA stabilised shock chlorine POWDER



Nissan Hi-Lite 90% TCCA stabilised shock chlorine GRANULAR  and POWDER. 7 kg. Very high quality. 



PoolChlor 90% TCCA stabilised chlorine GRANULAR. The next highest quality brand of chlorine available in Thailand 



PoolChlor 90% TCCA stabilised chlorine POWDER 

PoolChlor 90% TCCA stabilised chlorine TABLETS. Very high quality. No wasrefull fillers or binders. 



Dichlor 60%. SDIC stabilised poolshock GRANULAR Ideal for for shocking pool with salt water chlorinators, or starting a new pool or a newly filled pool.



Calcium Hypochlorite 65% non-stabilsed pool shock POWDER Non-stabilised fast-acting chlorine 65% for shocking pool water without increasing the CYA level.



Cyanuric Acid (CYA) prevents 'burn off' of non-stabilised chlorine by harsh tropical sunlight. Most chlorine products for pools are stabilised (trichloroisicyanuricacid, trichlor, TCCA), that is, they already contain CYA Only small quantities of CYA are needed. A useful additive when using salt water chlorination systems because they do not produce stabilised chlorine, but expensive and difficult to obtain in Thailand. The simple workaround is to either run the salt water chlorinator during the hours of darkness, preferablt at dusk, or to occasionally add a chlorine tablet to the skimmer. Read more in our CYA Fact Sheet.



OTHER CHEMICALS stain removers, filter cleaners, toilet & terrace disinfectants



FilterKleer swimming pool filter cleaner and degreaser for cleaning, regenerating, and rinsing sand, Zelbrite, glassmedia, D.E. grid elements, and cartridge filters.

NanoKleer chlorine-free pool liquid santitation system. A revolutionary chlorine-free swimming pool sanitiser designed for easy cleaning and maintenance of small pools.


Pool Salt TRS (Blue bag)
 Specially refined for use in swimming pools with salt water chlorinators, and brine bath spas. From Asia's largest salt mine - in Thailand. TRS pool salt does not contain any  additives that can damage chlorinator cell  electrodes. Using other salt or table salt will shorten the life of the electrode. Electrodes are very expensive to replace. 


SteriKleer disinfectant is essential for commercial and heavily used private pools. Disinfectant, fungicide, bactericide, and deodorant. Removes dirt, grime, grease and oils, preventing odour, and kills germs. Ideal for use on pool walls, steps, slides, spas, decks, patios, showers, and toilets. Kills many bacteria including Staphylococcus aureus and Salmonella typhosa.



CheliKleer stain & scale remover. Prevents and removes stains and scale by chelating minerals such as iron, calcium, and manganese.

StainKleer sprinkle StainKleer evenly around the water. Use 500gr of StainKleer for every 40,000 litres of water. See product page for full details.
NOTE: CheliKleer and StainKleer work particularly well with each other.

MANGANESE GREEN SAND is a zeolite filter medium. It is used for removing heavy iron, manganese and other metallic elements from well water. It is used as the filtration medium in well water filters.