Description
What Is a Refugium?
A refugium is a component of a reef tank’s filtration system that is separate from the main display tank. Generally reefers will use the refugium to grow macroalgae such as chaetomorpha or caulerpa. Refugium are a form on controlled algae growth. This macroalgae will absorb nutrients such as phosphate and nitrate, so it will out compete other nuisance algaes. In addition, a refugium can also be stocked with copepods and can provide a refuge (hence the name) for them to grow and reproduce. In an All in One system a refugium can easily be set up in one of the rear chambers.
Chaetomorpha is a common type of macro algae for refugium’s
What Is a Refugium Light?
Macroalgae’s that are grown in a refugium are all photosynthetic and require light in order to grow, so it is important that a refugium be equipped with appropriate lighting. The vast majority of refugium specific lights contain predominantly blue and red LED diodes, which provides light that appears violet or purple. This is different from main tank lighting, which tends to contain a larger variety of LED diodes. The Nova Refugium Light by Reef Casa is designed to provide the ideal light wavelengths for growing macroalgae. This light has the added bonus of dual mounting options, either by a traditional gooseneck arm or directly to the back of the Reef Casa lineup of aquariums for a more streamlined look.
The spectrum of the nova refugium light is specifically designed to promote algae growth
When Do You Use a Refugium Light?
Macroalgae will not survive without adequate lighting. Anytime you want to grow macro algae in a refugium you will need a suitable light. A refugium without the correct lighting will not be very effective and the algae is not likely to survive long term. If this happens the water quality can deteriorate, which very much defeats the purpose of setting up a refugium. A specifically designed refugium light producing the correct light spectrum is essential for an effective refugium.
Why Grow Macroalgae in a Refugium?
There are a number of benefits to setting up a refugium on reef tanks of all sizes. The first, and generally most often cited, reason is that a refugium is a highly effective way to reduce both nitrates and phosphates in the tank. As the macroalgae grows it consumes phosphates and nitrates and these elements are removed permanently from the tank when the algae is harvested. Since the macroalgae will outcompete most other forms of nuisance algae for these nutrients, having a refugium is a great way to reduce the amount of other types of algae in the display tank. This can lead to a cleaner looking tank and also, potentially, increase the period of time between water changes. Another benefit of a refugium is that they provide a habitat for useful microfauna. Hobbyists who keep species such as Mandarin Dragonets or Scooter Blennies will often set up a refugium to provide a place for the microorganisms required by those species to grow and reproduce. In this way a refugium can help to ensure a steady food source for some of the hobby’s pickier eaters. Many of these microorganisms will also help to control things such as diatoms and other nuisance algae.
How Long Do You Run a Refugium Light?
Generally, a refugium light is run for about 8-12 hours a day, ideally on a lighting schedule that is opposite from the main tank. This is because the pH levels in a reef tank tend to drop when photosynthesis stops when the main tank lights turn off. While these pH swings are not generally harmful to corals, adding a refugium on a lighting schedule that is opposite to the main tank can help to reduce or even eliminate them, leading to improved coral growth and coloration. It is vital that a refugium light not be run constantly, as this can damage the macroalgae and also contribute to the growth of nuisance algae. For this reason, 8-12 hours is generally considered to be the most effective time range.
What is the Best Type of Macroalgae For a Refugium?
There are many options for refugium macroalgae, but two of the most commonly used are chaetomorpha or caulerpa. Both of these algaes are widely available and fairly inexpensive. They are also considered to be hardy and are quite fast growing, which means that they will remove a large amount of nitrates and phosphates from the water. There are other options such as Dragon’s Tongue that are more interesting to look at visually but they are also generally more expensive and less hardy.
When Should You Start a Refugium?
A refugium should be started when the tank has matured and the levels of phosphates and nitrates are high enough to support the growth of macroalgae. While it is hard to put an exact time on when that will occur, due to variations in things such as the amount of livestock in a tank, it is a good idea to at least wait a few months before setting up a refugium.
Setting Up a Refugium on Reef Casa Tanks
At Reef Casa we have designed our tanks with an extra large rear chamber which makes a great place to set up a refugium. In addition to the Nova light we now also offer the Reef Casa Planter that makes setting up and cleaning your refugium a breeze.