The male of the harem goes to great lengths in protecting his territory from intruders (other males) and all members of the harem do their best (and it is much, considering their size) to protect the fry: similis will face fish as big as a Tropheus - if the latter become too curious - and will escape into their shells in a blink of an eye if the threat is deemed serious.
The tank decoration should take into account N. similis' — habits. All shell dwellers favor a sand substrate in the aquarium. All shell dwellers — (except N. brevis) benefit from many empty snail-shells. (In the case of N. brevis - which live in a part of Lake Tanganyika where shells are relatively rare - the male and female share the same shell.) Rocks can be used as background, but are irrelevant to the fish, except in cases of intense aggression; in such cases, the cover provided by rocks often saves the expelled fish's life. Plants - either real or plastic - can also be introduced, but should be weighted, for this fish is an untiring digger, digging sand pits in which to hide its shells from predators and thieves.
In Lake Tanganyika shell dwellers use the Neothauma tanganyicensis snail shell as their refuge. In the aquarium, any lightweight shell about the same size, such as a whale's eye shell, is acceptable to the similis, and much less expensive for the hobbyist.
N. similis accept almost any type of food, from flakes to small pellets, but are far better off if shrimp mix, live Artemia larvae, live mosquito larvae (red or black) or "Tanganyika Mix" are regularly provided.
This fish is reputedly easy to spawn. Clean, stable water, varied high quality food, minimum aggression, and a water change with the temperature one or two degrees above its normal will usually be enough to cause any fish to spawn, and Neolamprologus similis is no exception; indeed, once started, they will increase in number fairly rapidly. If the available space is adequate for only one harem, excess males must be removed before the harem's male injures or kills them.
Care must be given so that Neolamprologus similis does not crossbreed with the superficially similar, N. multifasciatus. Similis grow slightly larger than "multis", but unless all specimens in question have reached maximum size - and gender for each specimen is known - size is often a very difficult way to identify fish. The two species are much more easily identified by the following:
(1) N. similis stripes extend onto their heads, multis' stripes stop before the head.
(2) N. similis is a brown fish with white stripes; N. multifasciatus is a white fish with brown stripes; hence, multis are a ghostly white, while similis is a darker fish.