A twist on the refugium concept. The Xenia refugium.

Inspired by Jake Adams and Julian Sprung’s friendly debate on Refugiums last MACNA, I decided to remove algae from my Refugium and replace it with Xenia. I wanted to remove any nuisance algae as well as Chaetomorpha and Caulerpa, so I added urchins, snails, and tangs. I also decided to try 24-hour lighting for the benefit of a more stable pH. I wasn’t sure how the Xenia would respond, and I was ready to switch to a reverse day/night cycle if needed.

Much to my delight, the Xenia thrived and pulsed nonstop. There has been no bleaching and its growth rivals Xenia grown under normal cycles. In contrast to the continuously lit Xenia, the Xenia under normal light in the system take a few hours to start to pulse in the morning. This is another sign that the pulsing action of Xenia respires oxygen out of the coral to reduce oxidative stress. It helps the Xenia thrive under the 24 hour lighting; as the zooxanthellae photosynthesis more, the coral can remove its buildup of oxides. And it continually absorbs nutrients from the system.

Despite being lit 24 hours, this Xenia thrives, and is darker than 12 hour lit Xenia.

Enjoy the video below! My sump happens to be located in a thriving public aquarium, this sort of thing happens around my system fairly often. Is that a dog?