
Are you unsure which rainwater tank pump will work best with your water storage tank? We’ll look at different types of pumps, how they work, and what advantages each type has in this post so you can figure out which pump to use for your rain harvesting system.
Budget
So, if you’re wondering, “what sort of pump should I use for my rainwater harvesting system?” the first thing you should consider is “How much money do I want to spend?” because there are a variety of pumps available at various price points.
There are first the budget pumps, which are less expensive but less convenient to operate. Then there are the higher-end “on demand” pumps, which are more expensive but easier to use. Let’s have a look at how each type of pump works and the advantages they provide.
Pump Type
On Demand Pumps
This sort of pump is always pressured and pressurises the water to a faucet or irrigation system. When the pressure drops, built-in sensors detect it, and the pump immediately turns on. These higher end pumps stay on and pressurise the water all of the time, so you wouldn’t have to worry about tampering with an electrical outlet by flipping the switch. You can simply go up to your faucet, switch it on, and presto: pressurised rainwater.
Transfer Pumps
When you plug in this type of pump when you need it, it pressurises the water. You can’t leave these pumps running all the time. If you’re using a hose nozzle with these pumps, you won’t be able to stop the flow of water (by turning off the hose) while the pump continues to run. If the pump is not running with water flowing through it, it will overheat. A lesser cost economical pump would be an excellent choice if you want something easy, where you just flip a switch and when you’re done using water, you can just flick the pump off.
Submergible & External Pumps
Submersible or external pumps can be used for both types of pumps (transfer and on-demand). It all relies on the unique pump’s design. External pumps will be installed outside of the tank, whereas submersible pumps will be located inside the tank (likely near the electrical outlet). Submersible pumps have the advantage of having a water level indicator that will automatically shut the pump off if the water level drops too low. Another consideration is that they are hidden from view. If you’re concerned about appearances, you’ll have to hide an external pump in a hole or under a cover.
Flow Rate, Pressure, and Electricity
You’ll need to figure out how much flow and pressure your system will need, as well as how much electrical power you have (as some types of pumps require higher voltage power). You’ll need to think about what you’re going to do with your water to figure out what flow rate you need. You must consider where your pump is located as well as how your system is built up when calculating your pressure (i.e. if you are pumping from underground to a few floors above ground it will need more pressure than a standard “ground level” system).