Welcome to the Clark Rubber Knowledge Centre
Your trusted hub for helpful guides, product advice, and practical information to support your next project.
Whether you’re maintaining your pool and spa or looking for expert guidance on the right products to use, our Knowledge Centre is designed to make things simple with clear, customer-friendly answers.
Browse the categories below to explore tips, how-to articles, and commonly asked questions, with helpful information to keep everything running smoothly and looking its best.
Browse By Pool & Spa Category
POOL & SPA FREQUENTLY ASKED QUESTIONS
Pool water testing tells you what your pool actually needs. Without testing, it’s easy to add the wrong chemicals, which can lead to cloudy water, algae, irritation, and wasted money.
A standard pool water test checks:
Free chlorine
pH
Total alkalinity
Stabiliser (cyanuric acid)
Calcium hardness
Salt levels (saltwater pools)
Some tests also check phosphates and metals.
pH levels indicate whether your pool water is too acidic or too alkaline, which directly affects swimmer comfort, chlorine effectiveness, and the lifespan of your pool equipment. Keeping pH within the recommended range helps prevent eye and skin irritation, protects surfaces from corrosion or scale, and ensures your sanitiser performs at its best for cleaner, healthier water.
Salt levels are crucial for saltwater pools because they allow your chlorinator to generate chlorine efficiently. When salt is too low, the chlorinator can’t produce enough sanitiser; when it’s too high, it may strain the system. Keeping salt levels balanced ensures consistent chlorine production, reduces maintenance issues, and supports sparkling, healthy pool water.
Total alkalinity is measured in parts per million (ppm) of carbonates and bicarbonate salts in pool water. It helps stabilise pH.
Glossary terms:
Total Alkalinity (TA) — The measure of carbonates and bicarbonate salts in water that helps stabilise pH.
ppm — Parts per million. A standard unit used to measure small concentrations of chemicals in water (for example chlorine, alkalinity, hardness and stabiliser).