Cryptocentrus cinctus - The captive bred Yellow Watchman Goby is a beautiful goby that naturally varies in color. This is the grey morph. Both in the wild and in captivity, this species can be mustard, pale with olive-grey bands, or bright yellow, all with iridescent blue dots. Feeding a diet heavy in astaxanthin and carotenoids can help them to retain their bright coloration. Gobies on lighter colored substrates also tend to be brighter over time. Hobbyists even sometimes witness their gobies changing color in their tanks. Having one of each color would make an interesting display in a home tank.
Watchman Gobies are well-behaved reef inhabitants that will not pick at coral, sessile invertebrates, or other species of fish. Avoid keeping it with aggressive species or animals that are large enough to eat small fish. Like other gobies, these can easily jump out of an aquarium when chased or frightened, so a tight fitting lid is required. With a max size of 4" they require an aquarium of at least 30 gallons. Though they are peaceful fish, they will use their large mouths to display or push other fish away from their burrows. They are territorial toward other shrimp gobies, so be sure to give each goby adequate room for territory if you're keeping more than one shrimp goby. We recommend introducing new fish with an acclimation box.
Our captive bred Watchman Gobies are feeding on Easy Reefs DKI pellets, Hikari frozen mysis, and Hikari frozen Calanus. These gobies are carnivores, and we recommend a varied diet of small meaty foods and pellet. While the gobies are still growing, feed at least 3 - 4x a day.
Watchman Gobies get their name from their symbiotic relationship with certain species of pistol shrimps. Unfortunately at this time, the pistol shrimp are not aquacultured. The Gobies do not require a symbiotic shrimp for survival in the home aquarium.
The symbiotic relationships these gobies form with their shrimps is fascinating. The shrimp builds and maintains the burrow where shrimp and goby live. In turn, the goby provides protection and food for the shrimp. When the two are together, you'll notice the shrimp always has an antenna touching the goby, as this is how the two communicate. When danger approaches, the goby will signal to the shrimp that it must retreat into the burrow immediately, and the goby follows quickly after. This allows the shrimp, which has poor eyesight, to work on the burrow without having to worry about also watching for predators. In the wild, it's common to find a pair of gobies and a pair of shrimp inhabiting one burrow together.
There are a handful of species in the aquarium trade that naturally pair with Watchman Gobies, though only a few are commonly available. The Yellow Watchman Goby will pair with Alpheus bellulus,Alpheus randalli, Alpheus ochrostiratus, or Alpheus djiboutensis. The shrimp relies on chemical cues to find and pair with a goby. Keep in mind, most species of Alpheus are not goby symbionts; some form relationships with invertebrates like anemones, sponges, or corals, and others are free-living. Though it is possible for a goby to "adopt" a species of shrimp that is not a natural symbiont (occasionally even a peppermint shrimp!), it's much less likely, and the behaviors will be different than they'd be with a natural pairing.