Shell dweller care: keeping multies and other shell-dwelling cichlids

Shell dwellers are tiny cichlids from Lake Tanganyika that live in empty snail shells. They dig, guard their shells and raise their babies in the open, so a small colony is one of the most interesting tanks you can keep. They just need hard water, sand and plenty of shells.

I keep a shell dweller tank myself and have bred them in it. It's one of only two of my 18 tanks without live plants, because these fish move sand all day.

Shell dweller facts

• Most common species: Neolamprologus multifasciatus, called "multies"
• Size: males about 1.5 inches, females about 1 inch
• Tank: a 20 gallon long is ideal for a starter colony. A 10 gallon can hold a single trio.
• Temperature: 75–80°F
• Water: hard and alkaline, with a pH of about 7.8 to 9
• Group: start with 6 young fish, or 1 male with 2 or 3 females
• Lifespan: about 5 to 8 years

Which shell dweller?

Multies are the easiest place to start. Watching a colony of them is the reason most people get hooked.

Setting up the tank

• Sand, at least 2 inches deep. Shell dwellers dig pits and bury shells to the rim. Aragonite sand also helps keep the pH and hardness up. See the substrate guide and work out how much you need with the substrate calculator.
• Lots of empty shells, at least two per fish. Cleaned escargot shells (sold for cooking or for aquariums) are the right size. Never use shells with a living snail inside.
• A few rocks at the back break up sight lines so each fish can claim a corner.
• Gentle filtration. A sponge filter or a small hang-on-back filter works well. The fish are small and don't make much waste.
• Hard plants only, if any. Anubias and java fern tied to rock survive the digging. Rooted plants get dug up.

Water: hard and steady

Tanganyika is hard, alkaline water. If your tap water is soft, aragonite sand, crushed coral in the filter, or a mineral salt made for African cichlids will raise the hardness. Test pH weekly at first with a liquid kit. Do a 20 to 25% water change each week, using a water conditioner. Cycle the tank before adding fish (see how to cycle a fish tank).

Feeding

Shell dwellers eat small meaty foods. A good small pellet or crushed flake as a base, plus frozen baby brine shrimp, cyclops or daphnia a few times a week, keeps them colorful. They feed from the water column near their shells, so let food drift slowly instead of dumping it in one spot.

Behavior and breeding

Each fish claims a shell or two and defends a small circle around it. Males are bigger and guard a few shells, each used by a female. Females lay their eggs inside the shell, and the fry appear at the shell's mouth a couple of weeks later. In a healthy colony this happens on its own, and the fry are usually left alone by the adults. A colony grows slowly over months, so plan where the extra fish will go before the tank fills.

Tankmates

Many keepers give shell dwellers a tank of their own. In a 30 gallon or bigger, other Tanganyikan fish that swim higher up, like small Cyprichromis or a pair of Julidochromis, can share the tank. Avoid soft-water community fish like neon tetras, and anything big enough to eat the fry. Check other fish with the fish compatibility checker.

Related: Aquarium pH · Best aquarium substrate · Fish care sheets