How to Maintain a Fibreglass Pool in Cape Town (the Easy Way)

By Aquatic Pools
June 2, 2026

One of the biggest reasons Cape Town homeowners choose a fibreglass lining is how little upkeep it needs. The smooth, non-porous surface gives algae nowhere to grip — but fibreglass does have a few care rules that differ from marbelite. Follow these and your pool will stay sparkling with minimal effort.

Why fibreglass is easier to maintain

Non-porous — algae and dirt can’t penetrate, so you brush less and use fewer chemicals.
Smooth gelcoat — debris wipes away easily.
Stable surface — no constant re-plastering or acid-washing like marbelite.

Your simple fibreglass pool routine

Weekly:
– Skim leaves and empty the skimmer and pump baskets
– Brush the walls and floor with a soft (nylon) brush — never a steel/wire brush
– Test and balance the water
– Check the pump and filter are running well

Monthly:
– Backwash or clean the filter
– Check salt/chlorinator levels
– Inspect the waterline for oils and give it a wipe

Water chemistry for fibreglass pools

Keep these in range:

pH: 7.2 – 7.6
Total alkalinity: 80 – 120 ppm
Free chlorine: 1 – 3 ppm
Calcium hardness & stabiliser within recommended levels

Avoid over-chlorinating or letting chlorine sit high for long periods — it can dull or discolour the gelcoat over time. Balanced, consistent chemistry beats big swings.

What NOT to do with a fibreglass pool

❌ Don’t drain it unnecessarily. An empty fibreglass shell can lift or “pop” out of the ground from hydrostatic pressure (see our guide on draining a pool in Cape Town).
❌ Don’t use a wire brush or abrasive pads — they scratch the gelcoat.
❌ Don’t acid-wash it like marbelite — fibreglass doesn’t need it and it can damage the finish.
❌ Don’t let chlorine run very high for extended periods.

Seasonal care in Cape Town

In summer, run the filter longer (8+ hours), keep chlorine up against the heat, and shock after heavy use or rain. In our wet winters, you can reduce filtering but don’t neglect the pool — follow our month-by-month maintenance calendar.

Keeping the gelcoat looking new

A fibreglass finish holds its colour for years. Keep balanced water, wipe the waterline, and every so often a fibreglass-safe surface polish restores shine. Looked after, a quality lining lasts 15+ years.

How a fibreglass pool saves you money

Lower chemical use, less running time fighting algae, no regular re-plastering or acid-washing, and a 15+ year lifespan all add up. Over a decade, a fibreglass pool typically costs noticeably less to own than a marbelite pool that needs redoing every 7–10 years — on top of being far less hassle week to week.

Common fibreglass pool mistakes to avoid

The biggest mistakes we see are draining the pool unnecessarily (flotation risk), scrubbing with abrasive or wire brushes, letting chlorine sit very high, and ignoring water balance until algae appears. Avoid those four and a fibreglass pool is genuinely close to effortless.

Frequently asked questions

How often should I service a fibreglass pool?
A quick weekly check (skim, brush, test, balance) plus a monthly filter clean is enough for most pools; many owners add a periodic professional service.

Do fibreglass pools ever need resurfacing?
Eventually the gelcoat can dull after many years, but a quality lining lasts 15+ years — far longer than marbelite between resurfaces.

Is a fibreglass pool low maintenance?
Yes — the non-porous surface resists algae and staining, so it needs less brushing and fewer chemicals than marbelite.

Can I use any brush on a fibreglass pool?
Use a soft nylon brush only. Wire or stiff brushes scratch the gelcoat.

Should I drain my fibreglass pool to clean it?
No — draining a fibreglass pool risks it lifting out of the ground. Clean and balance it full; only drain for professional resurfacing with the right precautions.

What chemicals does a fibreglass pool need?
The usual — chlorine, pH and alkalinity adjusters — kept consistently in range. Avoid prolonged high chlorine that can affect the gelcoat.