When buying a rainwater tank you will also need fittings and accessories, some are mandatory while others are recommended. The purpose of this article to help you understand what fittings and accessories you should consider for your water tank.
While not a fitting or accessory, it is a very important extra to consider doing right, no matter what rainwater tank you end up purchasing. Keep in mind our poly tanks are strongly built and exceed Australian standards (AS/NZS 4766). Nonetheless requirements for installing Clark Tanks’ poly tanks include:
- uniform compact base on level ground that is free from soft spots
- all bases should be at least 200mm greater than the diameter of the tank (i.e., 100mm greater all around the tank)
- where applicable, that the base has some sort retainment to prevent erosion
- tank slabs should be 100mm thick and comprised of compacted crusher dust or 100mm reinforced concrete (water tanks greater than 36,000 litres should have a 150mm thick concrete base)
Pause and think for a moment about your water tank and how water will flow into it, where will excess rainwater flow once your tank is full and then how you will access the rainwater in your tank? At a minimum, you will require three holes in your water tank as follows:
- Tank Inlet – where rainwater flows into your tank, often a hole in the top of your tank where you place a strainer with a tight seal to keep out mosquitoes and debris.
- Tank Outlet – located at the bottom of your tank where a ball valve is fitted connected to a flexible rubber hose that can absorb any shock and movement (preventing excess strain on fitting and tank wall).
- Tank Overflow – at the top of your tank where PVC piping is connected to allow excess rainwater to flow out of your tank, away from your tank base and into stormwater drainage.
Important: these points can be entry points for animals and insects into your tank and so require adequate screening.
Tank Strainers and Screening
Food-approved strainers should be placed at the top of your tank where rainwater flows in, as they stop leaves, insects, frogs, mosquitoes and the like from entering your tank. Overflow screening should also be had.
Leaf strainer covers can also be purchased, stopping sunlight entering your water tank which keeps your water algae free.
Rain heads (leaf eaters) also help to deflect leaves and debris away as the rainwater comes down your gutter into downpipes that lead to your water tank.
Gutter guards can also be purchased to further prevent leaves from clogging and/or making their way into your gutters and down into the pipes which lead to your rainwater tank.
Tank Pumps and Pump Covers
You will need a water pump to access your rainwater around your house and property. In addition, you should purchase a pump cover specially designed for your pump to ensure it receives maximum protection from the weather. Electric pumps are by far the most popular.
Rainwater to Mains Water Switch
Have you thought about what would happen if the rainwater in your tank ran dry while being connected to your toilet, laundry or shower?
The solution is installing a rainwater to mains water switch. This allows rainwater to be used as your primary water supply, but your mains water supply gets used once your rainwater runs low. An automatic switching device is recommended which can actually help reduce your mains water usage by 40%.
Downpipe Water Diverters (“First Flush”)
“First flush” water diverters help to prevent the initial run-off of roof rainwater entering your water tank. This first flush of rainwater often contains debris and leaves amongst other things and having a water diverter prevents such from entering into your tank water.
Tank Self-Cleaning System
When harvesting rainwater in your water tank you want to ensure that it remains clean, fresh and safe. Organic particles from leaves and the like often find their way into your tank and turns into a sludge at the bottom of your tank.
Every three years it is recommended that you clean this out, especially if using your rainwater for drinking purposes. This often means paying a professional to clean your water tank or attempting the difficult task yourself.
Thankfully, there is a simple tank cleaning system that can be setup inside your tank so that when it reaches full capacity the sediment at the bottom of your tank is automatically expelled through your overflow pipe.