Drinking filtered water is proven to have its benefits, such as reducing your chances of developing kidney stones, improving digestive health and boosting the immune system - not to mention, many simply prefer the taste!
Of course, if you’re looking into investing in a water filtration system, then you’ll notice that there are many options available. One such option is a tankless reverse osmosis system, but how does this differ to traditional systems that come with storage tanks, and which is the better option?
We’ll cover just that in this guide, discussing the differences and pros and cons of these two types of systems and how to determine which may be the best solution for you.
Comparing Types of Filtration Systems
What is a Storage Tank Water Purifier?
Traditional reverse osmosis (RO) water filtration systems, come with a post-filtration storage tank. This storage tank sits underneath your sink and consists of a metal canister that features a pressurised rubber bladder inside, which holds the filtered water.
The reason for this pressurised tank is because the flow rate of filtered water to the tap is much lower than that of water coming out the tap straight from your plumbing system. The RO system will continue to filter water until the storage tank is full, then the storage tank will directly deliver water to the designated faucet when required, which it does at a higher pressure than the filter could otherwise achieve if directly delivering filtered water in real-time.
As the tank is drained, it will eventually reach a threshold that will trigger the RO system to start filtering water again to fill up the tank once more.
What is a Tankless Reverse Osmosis System?
As its name suggests, a tankless RO system, also known as a direct flow system, doesn’t use an under-the-sink water storage tank. Of course, these systems still need to overcome the issue of poor water flow.
The solution these systems use, then, is the inclusion of an electrically powered internal pump, which works to create the ideal pressure needed for efficient water filtering and processing. As a result, this system offers a steady and almost endless output of water, which is processed on demand and sent immediately to the faucet when required.
Pros and Cons of Tankless Models
Pros
Save Storage Space
One of the obvious and biggest advantages of a tankless RO system is that it requires much less space under your sink than a standard system that comes with a tank. The lack of a tank in tankless systems means that you have much more utilisable storage space under your sink that you can use for other purposes.
Endless Filtered Water Supply
Another key advantage of tankless models is that they provide an almost unlimited supply of filtered water at a consistent rate. This is because they process water on-demand thanks to the internal pump, so users don’t have to wait for more water to be filtered due to an empty tank.
Conserve More Water
Efficient tankless systems can save up to 34% more water than traditional systems, as they produce less wastewater. This can subsequently help save on your water bills, especially if your wastewater costs are high.
Can be Integrated with Numerous Add-on Features
Because tankless systems are powered using electricity, they can be integrated with a number of features that also use an electrical connection. For example, they can be fitted with smart faucets (these can offer reports on filter status), LED indicators and TDS meters (these indicate the number of total dissolved solids in the water).
Cons
More Expensive
Because of the advantages tankless systems offer over traditional systems, particularly their space-saving design and consistent supply of filtered water, they are naturally more expensive. Whilst they make for a worthwhile investment, this is something to consider if you’re limited by budget restraints.
Require Electricity to Operate
The internal pump that maintains an efficient water flow within tankless systems requires an electric connection in order to work. There are a couple of potential downsides to this; firstly, each time you turn on the faucet to get filtered water, the system will be using electricity, so you may see an increase in your electricity bill depending on how often you use it.
Second, if you experience a power cut at any point, then you would not be able to use your filtered tap as there would be nothing to power the internal pump. You would, however, still have access to water from your normal tap, it would simply be unfiltered.
Initial Output Can be Slower
Because tankless systems filter water on-demand, the initial output of water can be a little slow whilst the pump is engaged, meaning you may have to wait a short moment each time you use your filtered water faucet after periods of it not being used.
Concerns Over TDS Creep
Because of the slow initial output, there are some concerns that ‘TDS creep’ can be found in tankless systems. This is when the system provides you with water with higher levels of total dissolved solids (TDS) in (aka unfiltered water) in the first few seconds of output before the pump has fully engaged.
Pros and Cons of Traditional Tank Systems
Pros
Cheaper Option
Whilst they have an extra component that needs to be installed (i.e. a storage tank), traditional RO systems tend to be much cheaper than tankless systems, making them a slightly more budget-friendly option.
Fast Output
Because filtered water is readily available in the storage tank, there is a faster output when you need to use your dedicated filtered water faucet compared to when using one connected to a tankless system. This is because the water has already been filtered, thus there’s no need to wait for a pump to be engaged.
Work Better with Connected Machines
Alongside being connected to a designated faucet, under-the-counter RO systems can also be connected to other machines that use water, such as ice machines and coffee machines.
Whilst it’s recommended to avoid connecting tankless systems to such machines, since they don’t produce enough pressure for the filtered water to be utilised by these machines effectively, traditional systems can be connected to them and will instead work much more efficiently with them than their tankless counterparts.
More Customisable
Traditional systems are also notably more customisable, as they can be fitted with additional features to optimise the health of your filtered water, such as UV light or remineralisation.
Cons
Require Lots of Space
Because they require the installation of a water storage tank, traditional RO systems take up twice as much space under the sink than tankless systems. These tanks are designed to hold roughly 3.2 gallons of water, making them rather large.
Have to Wait for Tank to Refill
You may find that you sometimes have to wait before you can get filtered water from your designated tap when using a traditional tank system. This is because the tank will need to be refilled again as it is emptied, meaning you must wait for more water to be filtered and are left with a lower output in the meantime.
Generate More Wastewater
Whilst tank systems offer an ideal water pressure, they are still less efficient than tankless systems, meaning more wastewater is sent down the drain as they work, which has the potential to negatively impact your water bill.
Possibility of Bacterial Growth
Overtime, there is a possibility of bacterial growth developing within the water storage tank that comes with these systems. This is nearly impossible to visually detect, but the longer water stands inside the storage tank without being flushed out and replaced, the higher the chance of bacteria growing.
As such, these systems also require more frequent maintenance, such as more regular replacements of filters and sanitisation of the storage tank.
The Bottom Line: Which Should You Choose?
So, which RO filtration system should you choose? Well, there are multiple factors to take into consideration, such as:
- Budget limitations
- Space availability
- Your requirements from your filtration system
If, for example, you have a tighter budget, or simply want to choose the more cost-effective option, then you may want to consider a traditional tank system - as long as space under your sink allows for it.
Alternatively, if you are more limited on space and your budget allows, then a tankless system may be more fitting for you. This is also a more preferable option if your expected daily filtered water consumption is high. If you also value wastewater efficiency and are drawn towards the additional benefits of smart features, then you would likely get on better with a tankless system.
Direct Flow Reverse Osmosis Systems from Hommix Ltd
Whichever solution you opt for, we’ve got the system for you here at Hommix. Our reverse osmosis systems will rigorously remove most pollutants, going beyond the abilities of typical water filtration systems to give you clean, great-tasting water every day.
Browse our selection of standard and direct flow systems today, or get in touch with a member of our friendly team for further advice, information and assistance.
