Rainwater tank pumps

 The following models scored the best results in our test.

About the rest

The other pumps had lower flowrates, but were mostly still OK at 10–14L/min. You’d probably be reasonably happy with most of them. The one exception is the Rivaflo, which only achieved a very slow 6L/min.

We also tested the Aldi Garden Pump Gardenline AGFWP-800, which is now no longer available. Its flowrate was 14L/min, and it scored 75%. Priced at only $99, it was good value if you bought one.

Photos of the pumps are shown below so that you know what you’re looking for when buying, but we've only noted particular good and bad points for each that aren’t shown in the table.  Prices are recommended retail, as advised by manufacturers in August 2007.

Profiles - what to buy

Gardena 4000/5 Jet

Price: $383

Type: External

Comment: While it is noisier than the other models, it’s not especially annoying.

Grundfos MQ3-45

Price: $908

Type: External

Comment: Heavy and bulky and has no carry handle, but this wouldn’t be a problem if it was permanently installed.

Onga Dominator 4” 75/35 P3200100

Price: $654

Type: Submersible

Comment: Quiet, compared to others. 

BIANCO PUMPZ BIA-INOX 80 PC

Price: $463

Type: External

Dab Pumps DAB-JINOX62MPCX

Price: $701

Type: External

Davey HP45-05T

 
Price: $720

Type: External

Grundfos JP Basic 2 PC

Price: $519

Type: External

Profiles - the rest

The remaining pumps had lower flow rates than the best models, but were still mostly OK. You'd probably be be happy with most of these.  

Claytech Bluetron 100

Price: $415

Type: External

Davey SJ35-05PC

Price: $418

Type: External

Onga SMHP450

Price: $791

Type: External

Onga Tankbuddy OTB450A

Price: $514

Type: Submersible

Comment: Very quiet compared to the others. 

 

Dab Pumps DAB-KPS30-16MPCX

Price: $471

Type: External

Comment: Has an annoying high-pitched whirr sound.

Gardena 3000/4 Jet #

 
Price: $269

Type: External

# Discontinued.

Leader Ecotronic 90

Price: $300

Type: External

Onga SMH350

Price: $446

Type: External 

 

Bianco Pumpz BIA-TECH40PC

Price: $278

Type: External

Rivaflo TFM30

Price: $458

Type: External

Comment: Has an annoying high-pitched whirr sound.

What to look for in a pump

• Discuss your particular needs with an expert, such as a speciality tank and pump supplier. They should be able to recommend a tank and pump to suit you.
• Pumps that turn on and off automatically when you turn on the tap (or hose) are easiest to use. You’ll need a pump of this type if you connect it to indoor plumbing. Other pumps must be switched on or off manually, which is easy to do, but can be inconvenient.
• Multiple outlets on the pump allow you to run more than one hose, or a hose plus a plumbed-in connection.
• Run-dry protection prevents motor damage if the rainwater tank is empty.
• Submersible pumps are generally quieter than external pumps, as the water in the tank muffles their noise.
• A carry handle is useful if you need to move the pump between different sites, but isn’t necessary for permanent installations.

Installing a pump

None of the pumps in this test came with the necessary fittings and hose to connect them to a water tank. You have to buy those separately. The supplier should be able to recommend the right fittings.

You’ll need a weatherproof power point for the pump. If there’s none close to its location, have one installed by an electrician. Don’t connect the pump via an extension cord to an indoor power point, as this might not be weatherproof and could be unsafe.

All the pumps in this test are easy to install. For the external pumps, you just connect the pump inlet to the rainwater tank using a short piece of kink-resistant hose, secured with two hose clamps. The distance between tank and pump should be as short as possible. Next, prime the pump with water, plug the pump into the power and switch it on. Then connect a hose to the outlet and you’re ready to start watering.

For the submersible pumps, connect the outlet to your garden hose, then lower the pump into the tank (the Onga Dominator came with a length of rope for this purpose) and plug it into the power supply. Don’t use the power cord to lower or raise the pump.

Ideally, you should put a housing or cover over an external pump to protect it from the weather and muffle its noise. Most of the pumps in this test are about as noisy as a loud vacuum cleaner, and some have a high-pitched whirr that could be annoying.

There are plenty of good reasons to install a rainwater tank, even in areas that aren’t drought-affected. You will:

• Reduce your consumption of mains water and save money in the long run.
• Reduce stormwater runoff into drains, rivers and oceans.
• Harvest clean rainwater, which can be better than mains water for your plants and appliances, as it’s less salty. Many people think rainwater tastes better than mains water and makes a better cup of tea, too.

The key points for choosing and installing a tank are below. For more details, see our free buying guide to rainwater tanks.

Choosing a tank

There’s a wide range of sizes, shapes and even colours to choose from; talk to a few tank suppliers and shop around for a good price. If you’ve got limited space, a slimline tank at the side of your house can be a good option. Others include underfloor bladders and modular tanks.

As a general rule, bigger is better: you’ll be able to harvest more water when it rains, have more available for the dry times, and often you’ll get a better rebate too. Sydney Water recommends a minimum size of 2000L for basic usage such as a toilet connection or garden watering, and at least 5000L for tanks supplying water to both the toilet and washing machine.

Even with a 5000L tank, you’ll probably still be reliant on mains water, as a typical four-person household uses around 7000L of water per week.

Once you’ve chosen a tank, you’ll need to prepare the site. Choose a location out of direct sunlight if possible, to reduce evaporation from the inspection holes. You’ll usually need a concrete slab or a tank stand for the tank to sit on, and if you’re connecting it to your bathroom or laundry, you’ll need a plumber.

Installing a tank

First, check with your local council and mains water supplier for any rules and regulations that apply to rainwater tanks in your area. You might need a building application, or there might be restrictions on the size and location of the tank. Pumps might have to conform to noise regulations.

Also check whether you’re eligible for any rebates or other cost savings. Most states and some city councils offer rebates for installing a rainwater tank, but conditions apply. For example, in NSW the tank must be at least 2000 L in capacity to qualify for a rebate, and additional rebates apply if you connect the tank to your toilet or washing machine.

Your roof and gutters might be a consideration, especially if you plan to drink the rainwater. Older painted roofs might contain lead. If you live in an area with heavy traffic or industry, the roof might collect a lot of pollution. Make sure your gutters have guards to stop leaves and other matter getting into the collected water, and consider installing a first flush device to stop the initial run-off (which is likely to contain roof contaminants) from entering the tank.