There is no skimmer by Oceanic for the biocube that I know of. Several skimmers will work, with the Sapphire and Tunze the most popular. The Sapphire is a great fit, nice flow of bubbles, and well made. Some people have reported constant microbubble problems, but I do not have them. The Tunze is well made with an excellent reputation to back it up. It requires a modification to the tank to hold the collection cup. Some people (myself included) are not willing or able to make such a mod. HTH