Normally, when you hear the word “cichlid,” the first thing you probably think of are larger, more aggressive fish. Yet there are many surprises in this huge family of fish. Some of the most interesting are referred to as dwarf cichlids, which are neither large, nor aggressive, but they still display many of the great characteristics that make the cichlid family so popular. They are intelligent, easy to care for, make excellent parents and are not too difficult to breed.
The big eye shellies (Neolamprologus similis) are one of these wonderful dwarf cichlids. They are found in the southern part of Lake Tanganyika and are known in the hobby as “shellies” because they usually make their homes in the huge piles of snail shells that accumulate on the bottom of this part of the lake. They live in vast aggregations called colonies, where often several hundred or even several thousands of fish of all ages will live in an area only a few yards across.
Males and females look so much alike that even experts can’t tell them apart. The only obvious difference among full-grown fish is that the males are bigger, reaching just less than 2 inches, while the females barely top 1 inch. When purchasing them, the only sure way to get both sexes is to start out with a group of a half dozen or so young fish, giving you a nearly 98 percent chance of getting at least one pair.
Be forewarned that buying a “pair” may or may not get you a true pair. The male is obvious, but the “female” might be a young male — so avoid the false economy of buying just a “pair,” and buy a group. The fish will do better, anyway, given that they live in large aggregations in the wild and find safety in numbers.
It’s easy to set up a home for them. If you do it right, the rest of their care and breeding will be easy. They do best in a species tank just for them. This should be 10 gallons or larger. The water should be hard and alkaline, with a high carbonate content. Measure this with a KH test. The ideal number for big eye shellies is 8 or higher. There is little need for aquarists to measure it though, as long as they add a commercial African cichlid salt mix will help provide ideal water conditions for them. Temperature should be about 78 degrees Fahrenheit.
The waters of Lake Tanganyika are clean and low in dissolved organic substances, so fish coming from this lake don’t tolerate neglect of aquarium maintenance chores very well. Make sure you perform frequent, large water changes. Fifty percent a week is a good average for a small colony. As the numbers grow, you might need to do a second water change each week. An effective filter is also essential for consistent water quality.
The bottom of the tank should have a very thin layer of fine sand. Cover this with a layer of snail shells up to two or three shells thick. You can save some money by finding bulk dealers of snail shells on the Internet. The type of snail doesn’t really matter, as long as the shells are about 11/2 to 2 inches. As an alternate, you can make artificial shells out of half-inch PVC elbows and caps, but this isn’t much to look at.
Big eye shellies eat plankton in the wild. Simulate this with tiny meaty foods, such as newly hatched brine shrimp, frozen and freeze-dried cyclops and finely ground carnivore-type flake foods. They will also take Daphnia and Moina.
If well cared for and well fed, these fish will reach maturity and start to pair off. They appear to remain in monogamous pairs, but because they all look alike and live so close together, it’s really hard to tell. The pairs will set up housekeeping in shells that are close together. The male guards the perimeter, and the female cares for the eggs and fry. I’ve never seen the eggs, as they are usually laid deep in the shell.
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The first time you’ll know there is a spawn is when the female suddenly appears with a small cloud of fry around her at feeding time. Spawns are usually small; a dozen to 20 or so fry are better than average, but a half dozen to 10 fry is typical. The female keeps the fry close for the first few weeks, letting them explore the nooks and crannies around their home shell, looking for food. If danger comes near (such as a net in the tank or a strange face at the glass), the tank goes from a beehive of activity to a ghost town in an instant, with only a few brave fish peering out of their shells to see if danger has passed.
When the colony starts to seem too full, it’s time to thin it out. Fortunately, big eye shellies are in great demand. If you have a good rapport with the owner of a local fish store, you will likely be able to trade them for food and other supplies.