New SPS Corals

One of my local fish stores was having a two for one sale on corals, to make room for a new order.  Well, I couldn't pass up the deal.  My favorite corals are SPS (small polyp stoney) corals. We picked up four in total.

Green Slimer from Bali

Pink Millipora from Fiji

Yellow Millipora from Bali

Blue Acropora from Fiji

As I was putting the corals into the tank, I noticed something moving within the Pink Millipora.  It is common to find tiny acropora crabs that live in SPS corals.  They are commensal and have a symbiotic relationship with the coral, as they eat most parasites (ie., red bugs) that would harm the coral.  However, there are some tiny crabs that are harmful to the SPS coral, as they eat the coral's polyps.  I found a tiny gorilla crab, which is harmful, and so I picked him out and into the sump he went.  The common rule is: "If the crab's exterior is smooth, its friendly.  However, if the crab's exterior is hairy, its harmful".  Here is the gorilla crab before I threw him into the sump.