Calstop New Concentrated Formula 1.9 L - Calcium Reducer

Calstop New Concentrated Formula (1.9L) is Australia's leading calcium scale inhibitor for salt and freshwater pools. The new concentrated formula replaces the old 5L bottle and treats pools up to 50,000 litres, lasting up to six months per dose.

Key Benefits

• Holds calcium in suspension up to 1,000ppm — prevents scale formation
• Lasts up to six months per treatment
• Softens calcium scale in salt cells, making them easier to clean
• Recommended for all pool surfaces — concrete, pebblecrete, Quartzon, fibreglass, vinyl
• Ideal for new pools during the critical 4-week start-up period
• Treats pools between 40,000 and 50,000 litres per 1.9L bottle

How Calstop Works

Calcium is a naturally occurring mineral that can cause scaling and cloudiness when levels exceed 400ppm. Calstop keeps dissolved calcium in liquid form, preventing it from solidifying and scaling on pool surfaces, salt cells, and equipment. It is a preventative treatment — it does not remove existing calcium scale.

New Pool Start-Up Guidance

New pools with rendered finishes are most vulnerable to calcium build-up in the first four weeks after filling. Add Calstop as soon as the pool is filled. Key reminders during start-up:

• Do not adjust calcium hardness (CH) until after 4 weeks
• Monitor and maintain pH below 8.0 daily in week 1, then every 2–4 days through weeks 2–4
• Test total alkalinity weekly and keep above 100ppm
• Do not add salt within the first 4 weeks — use stabilised liquid chlorine instead
• Brush walls and floor daily with a nylon brush to remove residue

Frequently Asked Questions

What is Calstop used for?

Calstop is a calcium scale inhibitor that keeps calcium dissolved in pool water, preventing it from depositing as scale on pool surfaces, waterlines, salt cells, and equipment. It is a preventative treatment — it does not remove existing calcium scale.

How long does Calstop last?

One dose of Calstop 1.9L lasts up to six months and treats pools up to 50,000 litres.

Does Calstop replace the old 5L bottle?

Yes — the new 1.9L concentrated formula replaces the old 5L Calstop bottle. The concentrated formula delivers the same treatment capacity in a smaller, easier-to-handle bottle.

Is Calstop safe for fibreglass pools?

Yes — Calstop is recommended for all pool surface types including concrete, pebblecrete, Quartzon, fibreglass, and vinyl lined pools.

Can Calstop be used in salt pools?

Yes — Calstop is suitable for both salt and freshwater pools. It also softens calcium scale in salt cells, making them easier to clean and extending cell life.

What is the maximum calcium hardness Calstop can handle?

Calstop holds calcium in suspension up to 1,000ppm, well above the typical recommended pool range of 200–400ppm.

Downloads

• Calstop — MSDS Safety Data Sheet (PDF)