How Often Should I Change My Reverse Osmosis Filter?

Regular filter changes are essential to the proper function of your reverse osmosis system. Depending on the quality of water going into your system and your total water usage, you may need to change the filters more often than the standard suggested schedule. Here are some tips and tricks for knowing when to change your filter, and how to do it properly to extend the life of your system and maintain optimal water quality for you and your family.

Nu Aqua 5 Micron Sediment Filter

The sediment filter is your first line of defense against sand, silt, rust, dirt and other debris. This filter plays an important role in prolonging the life of your reverse osmosis system.

By keeping these larger particles out of the other filters, it extends their filtering capacity by preventing premature clogging in the other stages.

If you have well water heavy with sediment, your pre-filter may need to be changed as often as every six months.

If your water has low turbidity, it may only need to be replaced once per year.

With Nu Aqua’s transparent sediment filter housing, it’s easy to monitor sediment buildup in the chamber and replace the filter when needed, which is usually around 6-9 months.

Granular Activated Carbon (GAC) Pre-Filter and Coconut Carbon Block Filter

Filtering your water through granular activated carbon filters is crucial to protecting your reverse osmosis membrane. Nu Aqua offers not just one, but two carbon pre-filters, in their 5-stage systems.

The Nu Aqua Granular Activated Carbon (GAC) filter removes chlorine from municipal water supplies before it can reach the membrane. The water is then run through a second, coconut carbon filter, to remove any remaining traces of chlorine before it moves to the next stage.

If these filters are allowed to wear out without being changed on time, it could result in chlorine reaching the delicate reverse osmosis membrane, causing it to break down quickly and result in system failure. With patented HydraCoil™ technology, which allows for greater chlorine absorption, Stage II and III carbon filters are some of the best on the market.

It is recommended that you replace these filters every 6 months to 1 year, depending on the level of chlorine, pesticides, and other chemical contaminants you are removing.

Reverse Osmosis Membrane

This reverse osmosis membrane filter is the star of the system. It removes finer dissolved solids, including heavy metals, minerals, pesticides and salt from your water. Thanks to the hard work of the pre-filters, the membrane should last more than a year, and up to three years if starting from softened water. Hard water puts more stress on a reverse osmosis filter, so again, the lifespan of the membrane will depend upon the water quality going in.

If your water output suddenly becomes sluggish, or you begin to notice and flavors in your reverse osmosis water, it is a sign that at least one of the filters isn’t working properly.

Routine testing of your water with a Total Dissolved Solids (TDS) meter will help you identify performance issues immediately before they progress or become worse.

If the rejection rate for your water drops below 80%, as measured by your TDS meter, it’s a sure sign that your RO membrane is failing. A properly working reverse osmosis system should produce water that is of 99% percent purity or higher.

All Nu Aqua Platinum Series reverse osmosis packages come with a complimentary TDS meter included, so that you can test the quality of your water on a regular basis and know immediately if your system needs maintenance. Thankfully, RO membranes only need to be replaced every 1-2 years.

Carbon Polishing Filter

Nu Aqua’s T33 finishing carbon polish filter uses activated coconut shell carbon in granulated form to put a finishing touch on the water before it comes from the faucet.

Since the only water going through it has already been purified, it doesn’t have much work to do compared to the others.

This filter should only need to be replaced about half as often as the pre-filters, or every 1-2 years.

Flushing the System

When replacing your filters, consider cleaning the filters and running a sanitizer through the tubing and storage tank. This will help prevent the buildup of bacteria, slime, and other nasty stuff. First, turn off the water input valve and completely drain your storage tank. Remove all the filters from their housings, including the RO membrane and polishing filter—even if they’re not being replaced—and screw in the housing covers without the filters installed.

Before reattaching the first stage housing, however, pour about 1 cup of hydrogen peroxide into it. Turn the water input on and let the storage tank fill.

Turn on your reverse osmosis faucet and let the tank drain and then fill once more. Switch your input valve to the ‘off’ position, drain your storage tank again, and then install and/or replace the filters. Run your system through one more rinse cycle, and then you’re good to go!

Check out our convenient replacement filter sets, to help you keep your filter replacements on schedule. With proper care and reticular filter replacement, your reverse osmosis system will last for many years to come.