Chloramine is quickly becoming a concern for an increasing number of aquarium hobbyists because more and more municipalities are using chloramine to sanitize local water supplies.

According to the EPA, more than one in five Americans uses water treated with chloramine. If untreated, chloramine can get into your aquarium and have detrimental effects, ranging from excessive algae growth to the deterioration of fish and corals.

Because of this increasing concern among aquarists, we are going to give you guys the rundown on chloramine, teach you how to test for it and provide some helpful tips on how to remove it from your tap water.

Let's start by making it clear that chloramine and chlorine are not the same. While both chemicals are used to sanitize tap water, chloramine is much more stable and longer-lasting when compared to typical chlorine. This is the reason that more and more water treatment facilities are using chloramine instead of chlorine.

The problem for aquarists is that chloramine is not effectively removed by standard RO/DI systems and the presence of chloramine will quickly exhaust your DI cartridge.

In order to find out if your tap water contains chloramine, you can check with your local city hall or water treatment facility.

If you prefer to check yourself, you can test the waste water coming from your RO/DI system with a total chlorine test kit. Because standard carbon block filters remove all traces of chlorine, if your waste water still tests positive for total chlorine, it would mean that your tap water most likely contains chloramine.

As promised, we have some great solutions for getting rid of chloramine using your RO/DI system.

Since a typical carbon block cartridge will not remove chloramine effectively, a special chloramine removal carbon cartridge is needed.  We offer two different types on our website: the disposable chloramine removal cartridge and refillable Chloramine Blaster cartridge by AquaFX.  The refillable cartridge is especially economical because it can be refilled with the AquaFX Chloramine Blaster Catalytic Carbon Media.

Ideally, you will want to have two chloramine-removal carbon cartridges in-series after your sediment filter. Alternatively, you can use one chloramine-removal cartridge followed by one standard carbon block cartridge. By using two carbon block filters in series, you will ensure that no traces of chloramine enter the membrane or DI cartridge.

Since most RO/DI systems are not set up to accept dual carbon cartridges, it is likely you will need to modify your RO/DI system to install the appropriate carbon filters. We offer the Chloramine Blaster Upgrade Kit by AquaFX which includes all of the components needed to add the filters to your existing RO/DI system. You can also purchase the components separately on our website.

If you need help, please do not hesitate to contact our aquarium experts for assistance. We'd love to hear from you!

Until next time... take care and happy reefkeeping.


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