The fish in the photo is a belted wrasse, not a pencil wrasse, they are not the same thing. Belted wrasses get to be about 6", and require a 55gal tank for a healthy life. Often difficult to feed, even when eating it tends to waste away. Feed frozen meaty foods 3 times/day. Harmless to sessile invertebrates, but may eat more-delicate, smaller ornamental shrimp. In the wild, it feeds by taking mouthfuls of sand and spitting out the inedibles and lives on relatively small prey items, so a DSB, lots of live rock, and a healthy refugium are suggested. Will usually bury itself at night or when frightened. Males should be kept singly, but a male and one or more females can be kept together in a large tank. In comparison, the pencil wrasse does not get as big, only reaching 4.5" and requiring a 30gal. Overall, both are moderately difficult to keep, and should be housed with peaceful tankmates. HTH
