In my opinion, Lamprologus ocellatus is the most endearing of the cichlid species because of its small size, yet peculiar and often times spunky behavior. They are relatively unaggressive but highly active. Despite the fact that this little shell-dweller from Lake Tanganyika maxes out at 2-inches, the vigor with which it guards its territory is rarely matched.
In the wild, L. ocellatus inhabits the littoral zone - coastal regions where muddy or sandy shores are littered with empty shells of the snail Neothauma tanganicensis, at a depth of 15 to 100 feet.
In the tank, these cichlids should be supplied with at least one shell each. If you don't have access to Neothauma shells, escargot shells from a grocery store or delicatessen can be used as substitutes. Exercise care in selecting shells; don't use shells that are likely to "trap" a fish in its spirals. Each shell-dweller needs at least one shell because they use them for shelter from predators and as a site for egg laying and brood tending by the female. Even though you may not have any other fish in the tank, they will still hang out near and even cling to their shells. In other words, they are necessary to give these tiny fish a sense of comfort and well-being at a minimum.
If you don't provide enough shells, one of your fishes will get beat up and you'll probably find him ostracized to the upper corners of the tank. It's important to have at least one extra shell (if not more) so that the ocellatus have some choice among the shells. Furthermore, their young will need a shell once they get evicted from their mother's.
Males need an area of floor space with a 6-inch radius, which they guard vigilantly. This is not a ferocious cichlid, but neither is it afraid to attack intruders many times larger than itself. About two months after my first colony was established in their tank, I decided I'd add a few more shells. One dropped right in the center of the male's territory. He'd already claimed four shells and so I thought a fifth one was out of order and proceeded to put my hand in to move it. No sooner had my hand gotten within 5 inches of the shell before the male had bitten my knuckle. Needless to say, I ended up moving the shell with something other than my hand! ocellatus have even been known to attack Python siphons (see first video below).
For substrate, you can use either fine gravel or sand, but to truly experience the charm and intrigue of the ocellatus, you need to use sand. L. ocellatus, like all shellies, will excavate around its shell until it drops down level with the top of the sand, but where it differs from most is how it then buries the shell. It will (as demonstrated in the video) face away from its shell, open its mouth and plow into a pile of sand with a rapid, propeller-like motion, blowing sand backwards and covering the shell. I'm not sure why they hold their mouth open while they do this, but I'll admit that at first, I thought they were blowing the sand out their gills as they plowed into piles of sand.
Once you see the ocellatus's propeller stunt, you're sure to fall in love with this spunky little shellie. Konings in his 1998 video "Tanganykan Cichlids" suggested that the motivation behind shell-dwellers' restructuring efforts are two-fold. Foremost, they arrange the sand around their shell so as to build a rampart around the perimeter of their territory, providing them protection. Another possible motivation might be to create a catchment area that diverts the natural flow of water and plankton to the vicinity of their shell. This is important for the young fry who don't venture beyond the shell for at least the first couple of week
Lamprologus ocellatus has been called by some aquarists the "frog-faced cichlid" because of its protruding eyes and sloping nose. "Ocellatus," however, does not mean "frog face," but rather "eye spot." It was given this name because of the presence of a very distinctive spot, outlined in gold, on the fish's operculum. There are several varieties of L. ocellatus: gold, white, blue, orange, and yellow fin. The "Pearly Ocellatus" is often confused as belonging to this species because of its very similar appearance but has been assigned its own species classification - Lamprologus meleagris. The gold morph has a very distinctive, golden-brown sheen to the scales with a rose streak across its flank. It also has an unusual, light brown "skull cap" that sits across its head, just behind its eyes.
The primary difference among the sexes is that males are almost a half-inch larger than their counterparts. Males max out at 2 inches (5 cm) in total length and females at 1.5 inches (3.5 cm). Other differences are more subtle. Coloring is identical except females are supposed to have white-tipped dorsal and anal fins, whereas males' are gold. Males also tend to be more territorial than females, unless the latter are tending a brood. For example, females will usually let other females pass through their territory, although a visitor is often greeted with raised fins and only sometimes is chased off.