What Are Water Changes & How Important Are They For Nano Reef Aquariums ?

For reefers setting up their first nano aquarium, such as those available from Reef Casa, it can sometimes be overwhelming to sift through all the advice that is available.  While things such as lighting, flow and filtration are all important to a successful reef tank, the number one key to success is probably also the most simple.  Regular water changes.

While most hobbyists regard reefing as the keeping of corals, many successful reefers approach reefing as “the maintenance of water”.  What that means is that the number one way to increase the likelihood of reefing success is to maintain stable water parameters and the easiest way to do this is through regular water changes.  There is some debate about how much water should be changed and how often, however, a good rule of thumb for a nano tank is to change between 10%-15% every week.  Smaller, more regular water changes are preferable. So, while a 30% water change every two weeks is good, a 15% weekly change is better.

So why are regular water changes so important to any sized reef aquarium, but especially important in nano reef tanks?  First off, water changes are the most efficient method of removing harmful elements from the aquarium.  These elements include things such as nitrate and phosphates that can contribute to nuisance algae as well stunt coral growth.  A weekly 15% water change has been shown to prevent those elements from rising to problematic levels.  Water changes will also help to remove other chemicals from the water such as soaps that may enter the tank when a hobbyist inevitably has to put their hands in during maintenance or airborne chemicals from household cleaners.  In a smaller, moderately stocked nano aquarium regular water changes may also be sufficient to replace both major and minor elements, although calcium, magnesium and alkalinity should still be monitored and supplemented if necessary.  Regular water changes will also help to keep the aquarium water looking crystal clear.

Certainly regular water changes are not the only factor that contributes to a successful reef tank, but a consistent water change routine is probably the single most important thing that reefers can do to give themselves the best possible opportunity for success.