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Noticing algae growth in your reverse osmosis system can happen more often than you might assume.
It’s generally not a cause for concern, but it should still be dealt with promptly, as it can cause various health complications.
Here’s what you need to know about algae growing in your reverse osmosis system, how to deal with the problem, and how to stop it from reoccurring.
Here is what to do if you have algae growing in your RO system:
Algae can make its way into your reverse osmosis system either from your water source, or even directly from within the system itself. Algae isn’t very pretentious about the conditions it grows in, so it only takes a little for a full-blown growth to develop in a compromised part of your system.
Sourcing your water from a well is a very common cause of algae contamination. In fact, it’s something you will need to specifically address if you’re obtaining your water from a well in almost every case. After all, a well is the perfect environment for algae to grow in. Well water is full of contaminants that are useful to algae as nutrients, and it tends to have high pH levels and relatively little movement. All of those factors predispose to algae growth.
It’s also possible that the algae are coming from within the reverse osmosis system itself. As long as there’s a spot that offers the ideal conditions, all you need is a small initial growth.
There’s also the problem that reverse osmosis filtration may be a little too thorough for its own good in this case. Specifically, reverse osmosis systems remove chlorine and chloramine from water, which normally kills algae. This means that the later filter stages as well as the storage tank of your reverse osmosis system will likely be an ideal environment for algae growth.
The only way to get rid of algae in your reverse osmosis system is to thoroughly sanitize it. To do this, follow these steps – but also consult your system’s instruction manual, because there will likely be some steps that are unique to your own model and setup.
If you’re obtaining your water from a well, you must sanitize the well separately. Shock chlorination is the most popular method for accomplishing that.
Preventing algae growth is all about minimizing the factors that lead to it in the first place. This means that you should limit exposure to sunlight, and avoid having your water sit still for too long. Ideally, your entire filtration setup should be kept in a dark, cool place. That’s why many people use their basement for a whole house filtration setup.
You also need to keep your system clean and sanitized on a regular basis. If you don’t have particularly aggressive algae growths troubling you, it’s enough to do that every 6-12 months to stay on the safe side. And of course, make sure to replace each filter according to its prescribed schedule. Different filter elements have different requirements in this regard, so check the manual for more information.
If algae are still proving problematic, you may also want to revise your approach to water treatment slightly. Specifically, look into adding a UV filter or a chemical injection system to your setup. This will kill any algae and most other types of biological contaminants with a close to 100% efficiency.
This depends on the type of algae. Green algae are generally harmless, although it should still not be ignored.
Some specific types of algae can be very harmful to humans though, causing irritation, allergic reactions, and even producing toxic substances in some cases. These toxins are sometimes so strong that they affect not just the water they reside in, but everything else in that water as well. For example, you could get poisoned by eating seafood from a water reservoir with toxic algae growth.
Any signs of coloration in your water should be investigated in more detail. When it comes to green water in particular, many people’s immediate reaction is to assume it’s algae by default. But you should remember that green water can also be caused by another factor: corroding copper from your plumbing and making its way into your water.
This is especially problematic when you’re using a whole house reverse osmosis system, because reverse osmosis water is often slightly acidic and highly pure, and therefore more prone to corroding copper. What to do? Get the proper post-treatment in place. For example, a calcite filter will help you balance water pH levels and add some minerals back into the water.
If you have any questions about algae in reverse osmosis systems please don’t hesitate to leave a comment below!
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