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Testing kits & reagents at low prices for all our customers.

Pools, Spa, Hot Tubs

Our range of water testing equipment meets every application and budget. The range includes simple Block Testers for domestic pools through to Visual Comparators and Photometer-based Digital Systems for the more discerning users.  For details on which instrument would be best for your needs, please  contact us

The essential routine tests are for the disinfectant levels (normally Chlorine or Bromine), pH, Total Alkalinity and Calcium Hardness though many opt for the comprehensive Water Balance Kits.  

 The benefits of regular and accurate water testing ensures safety, reduced costs (chemicals are expensive) and, most of all, peace of mind.

 We supply Lovibond and Palintest test kits, reagents and tablets for a wide range of tests undertaken by those who care for swimming pools, spas and hot tubs

If you cannot find the test kit or tablets you are looking for then please let us know and we can get it ordered for you.

To ask any questions please email us

What should I be testing my pool for?

Besides the tests for levels of disinfection present the pool there are a number of other tests you may wish to consider.


The definition of pH, without getting too much into the complicated chemistry, is a measurement of how acidic, or how basic "alkaline" something is. The pH scale, registering from 0-14. Something with a pH of 7 or less is considered acidic, and anything with a pH of greater than 7 is considered basic or alkaline.

Many of the things that come into contact with your pool will have a similar pH rating to the water, but even minute differences in pH can have a measurable effect.

Why do I need to measure pH?

Most swimming pools using chlorine based disinfectants will aim for the sweet spot of around 7.2-7.4, with the best being 7.3  (Spa pools aiming for 7.0-7.2)

Outside of that range, especially if it starts getting far beyond that, it can quickly become hazardous to your bathers; causing eye and skin irritation, or serious physical harm if it’s considerably outside of that range.

Second, your pool pH level has a direct effect on the effectiveness of the chlorine in your pool.  The higher your pH the less effective your chlorine is at disinfecting your pool. So, if you have a pH of 8, whatever your chlorine level is will be less effective than the same amount of chlorine at a normal pH level.

What is Alkalinity?

Total Alkalinity, not to be confused with something alkaline is a measurement of the alkaline salts present in the water, it is an important measure separate from pH, but it does have an effect on pH.

Sophisticated science aside, it contributes to the stability of pH in your pool.

PWTAG guidance recommends the target ranges for swimming pools should be;

Sodium Hypochlorite  120mg/l – 150mg/l

Calcium Hypochlorite 80mg/l – 120mg//

Chlorine Gas 200mg/l

Why adjust Alkalinity?

If we have low total alkalinity in our pools, the pH will bounce around wildly, even with minimal factors influencing it. What this leads to though is a wasteful usage of chemicals. If we add acid to get our pH down, and it’s extremely effective, that’s great. Until, that is, we realize that what we added was too effective, and now we need to raise pH and the cycle then continues, bouncing back and forth above and below the desired range.

So having a total alkalinity that serves to anchor down your pH, and keep it from fluctuating wildly at every whisper of change can save you a lot of chemicals and money!

What is Calcium Hardness?

Calcium hardness is the amount of dissolved calcium in the water.  Hard water areas generally have higher amounts of dissolved calcium in the water, whereas soft water has low to no calcium.

In swimming pools we recommend calcium hardness levels be over 75mg /l as lower than this there is a risk of your pool becoming corrosive.  The general accepted range for Calcium Hardness is the region 100mg/l – 300mg/l however higher levels may be experienced in very hard water areas.

Why adjust Calcium Hardness?

Calcium hardness is important to have in your pool water at all times for one very simple reason. Water is hungry, and water that doesn’t have the calcium it desires will try to leach it out of anything it comes into contact with. Whether it’s getting it from your pool shell, your paint, your piping, or even the inner workings of your pumps!

The result of this would be brittle and breaking pool equipment and surfaces! But luckily it’s an easy fix!