We have added “Chaeto” to our refugium, which is short for Chaetomorpha. Chaeto is a type of algae whose main purpose is to help maintain good water quality, by filtering nitrates.
The type of Chaeto we have is Chaetomorpha linum and is ideal because it will not release nutrients or reproductive products into the water. Also, unlike other types of algae that attach to rocks or glass, Chaeto linum resembles a green tumble-weed, and when it grows too big can be reduced by simply “weeding” it down to a smaller size. This process of the Chaeto taking in waste products and then the aquarists removing the Chaeto is called “Nutrient Exporting”; one of the ways to help your little ecosystem thrive. Many aquarists sell or trade Chaeto after it has been weeded out to friends, hobbyist, or back to the LFS. Because Chaeto needs light to grow, we have added a light to the refugium on the opposite lighting cycle from the main tank, and have seen our small amount increase in size in just a few weeks.
The type of bulb we are using is a 100 watt daylight (6500K) compact fluorescent floodlight. It works great!
Adding Chaeto can also provide competition for other algae growing in our tank. We have recently had a diatom algae breakout in our display tank, and are curious to see how long it takes to die off now that we have added Chaeto and it is growing.
Chaeto can also play host to amphipods and copepods, which is great as we would like to acquire a Mandarinfish, which eats these live pods, in the near future.