Bullock's Sea Slugs are easy to spot with bright purple or fuschia bodies adorned with an opaque white edge on the mantle and yellow to orange gills and rhinophores typically. Some variation to these colors me be observed from specimen to specimen. This species is found in the western Pacific as far south as southern Queensland. It is also found in north western Australia, Thailand, the tropical western Pacific, and the eastern Indian Ocean, and is a common offering in the aquarium trade. These Nudis should only be housed in well-established reef aquaria where they may be able to find a food source, typically sponges, bryozoans or other specialized food items.
I'd get the serpent and green clown goby