Xenia

Xenia, famous for their mesmerising rhythmic pulsing motion, are one of the most captivating soft corals to watch in a reef tank. The pulsing behaviour — where individual polyps rhythmically open and close their tentacles — is unique among corals and endlessly fascinating. Place Xenia in the mid-section of your tank under moderate PAR (75–200 PAR) with moderate flow. Standard reef parameters are fine: alkalinity 7.5–9 dKH, calcium 400–440 ppm, and temperature 25–27°C. Interestingly, Xenia often pulse more vigorously when alkalinity is on the higher end of the range.

The main consideration with Xenia is their invasive growth habit. They spread rapidly across rockwork via stolons and can quickly colonise an entire aquascape if left unchecked. Many experienced Aussie reefers recommend placing Xenia on an isolated rock island surrounded by sand to contain their spread, or dedicating a specific section of the tank to them. If they do get out of hand, removal can be frustrating — fragments left on rock will regenerate. Some reefers report Xenia mysteriously crashing and disappearing from their tanks, while thriving in others under seemingly identical conditions.

Fragging is almost unnecessary as Xenia propagate themselves so readily, but you can easily detach branches and relocate them. They make excellent filler corals for new tanks, adding instant movement and life while slower-growing species establish. Xenia are widely available and inexpensive from Australian coral retailers and frag swaps. Despite their ease of care, the pulsing motion never gets old — they remain one of the most watched corals in any tank they inhabit.