Let’s be honest—no one likes jumping into an ice-cold pool, especially here in New Zealand, where the weather can be all over the place. But installing a fancy pool heater? That can cost a small fortune. The good news? You don’t actually need a heater to keep your pool warm. There are plenty of smart, low-cost ways to make the most of the sun and heat things up naturally.

Use a Solar Cover (a.k.a. Pool Blanket)

This is hands-down the easiest way to trap heat and warm your pool without a heater. A solar cover works like a giant plastic sheet that sits on the water and stops heat from escaping. It also cuts down evaporation, which means your pool holds onto warmth for longer.

If you don’t already have one, check out stores like Para Rubber or Swimart—they’ve got solar covers in all shapes and sizes.

Oh, and if you don’t want to mess around with taking the cover on and off all the time, look into a reel system. It makes life way easier.

Let the Sun Do the Work (Strategic Pool Placement)

If you’re still in the planning stages of building your pool, where you put it matters. A spot that gets maximum sun exposure throughout the day will naturally warm up a lot faster than one that’s constantly in the shade.

Already have a pool? You can still maximise sun exposure by trimming back any overhanging trees or shifting things that might be blocking sunlight, like fences or large garden features.

Try Solar Rings or Liquid Solar Covers

Not keen on dealing with a full-size pool cover? That’s where solar rings or liquid solar covers come in.

• Solar Rings: These are like floating solar panels for your pool. They’re smaller, easier to handle, and work by absorbing sunlight and transferring the heat to the water.
• Liquid Solar Covers: This sounds a bit sci-fi, but it’s just a thin layer of liquid (safe to swim in) that spreads over the surface and helps trap heat. You can find this stuff at places like Pool & Spa Warehouse NZ.

Black Hose Trick – DIY Solar Heating

Here’s a simple hack: Grab a long black garden hose, coil it up somewhere that gets a lot of sun, and run your pool’s water through it before it returns to the pool. The black hose will absorb heat from the sun, warming up the water before it re-enters the pool. It’s a free and easy way to boost the temperature, especially on hot days.

Wind Barriers (Because Wind = Heat Loss)

Wind sucks the warmth right out of your pool, so if your backyard is exposed, it’s worth putting up some kind of windbreak. This could be a fence, glass panels, hedges, or even shade sails positioned to block the breeze. Not only does this help keep your pool warmer, but it also makes swimming more comfortable on cooler days.

Dark Pool Liners (for Those Building a New Pool)

If you’re in the process of choosing a pool liner, go for a darker shade. Black, deep blue, or even dark grey will absorb more sunlight and naturally keep the water warmer than light-coloured liners. It’s a small detail, but over time, it makes a big difference.

The Bottom Line

If you want a warmer pool without cranking up an expensive heater, it’s all about working with nature. Use the sun, cut down heat loss, and add a few smart accessories to keep that heat where it belongs.

Try a combo of these methods, and you’ll notice the difference—without the massive power bill. Happy swimming!