In the almost-fifteen years that I’ve been keeping freshwater fish, I’ve usually selected species that aren’t shy– that like coming out to “play,” where they can be easily seen in the open. But, once I started keeping butterfly cichlids (also known as ram cichlids), these shy little critters did what they’re famous for: hid out inside the lava-rock caves I had set up throughout the aquarium. I knew that, like most cichlids and other shy, intelligent freshwater fish, ram cichlids need “dither fish” in their tanks in order to feel safe and at home.
A dither fish is a small, active fish that boldly ventures into the open spaces of an aquarium without hesitation. Over many millions of years of evolution, cichlids and other relatively intelligent fish have learned that water open water without little fish is a bad sign: in the wild, it means that a predator has recently passed through the area, either consuming the little fishies or scaring them into hiding. Water that is teeming with schooling fish, on the other hand, is clearly safe, so cichlids and other shy fish will happily swim out into the open to join them. Here are examples of excellent dither fish, especially for cichlids.
Small, schooling tetras are among the best dither fish because they join together in large schools. Many also prefer the soft, acidic waters favored by many cichlid species. Some of the most popular options are neon tetras and similar species (see Types of Neon Tetras for more information), which look stunning and form large schools. Harlequin and rummy-nose tetras are also good choices. Be sure to always keep neon tetras in schools of eight or more, and don’t house them with cichlids large enough to eat them (like discus and angelfish).
Zebra Danios and Variations
The zebra danio is a quick, active little fish whose fast-moving antics are likely to draw even the shyest cichlids out of hiding. They’re excellent dither fish because they’re so fearless and willing to brave open water (even when there really are scary, big fish around!). Zebra danios, which are top-feeders, are available in dozens of varieties, including gold, albino, leopard, and genetically modified “GloFish” varieties.
The dwarf gourami can be an excellent dither fish, especially for small cichlid varieties (like the ram cichlid and kribensis cichlid). Dwarf gourami do not form schools like most popular dither fish, but their small size and tendency to hang out in open water makes them interesting to cichlids. These little guys double as “target fish” for small cichlids, because they perceive them as competitors for territory and nesting ground. Small cichlids will often form strange “friendships” and territorial dynamics with dwarf gourami.
Several types of livebearer can act as dither fish. One popular option is the ubiquitous fancy guppy, which is as colorful as it is prolific. Fancy guppies swim readily in open water, and their tendency to breed easily (producing free, easy food for your cichlids) will tend to pull your cichlids out of hiding. Other livebearers, like the Endler’s livebearer (a close relative to the guppy), the molly, the platy, and the swordtail are also good choices and will add a nice splash of color to your tank.
Ultimately, the best dither fish for your aquarium will depend on a variety of factors, including the ecology of your tank. For example, guppies and small tetras aren’t good choices for tanks with large carnivorous fish, and you may need to choose either top- or middle-water feeders based on what niches in your aquarium are already claimed. Equally importantly, you’ll need to consider if your water parameters and temperature are suitable for your new dither fish. Once you’ve made the best decision based on the specific needs of your aquarium and its inhabitants, you’ll see your shy cichlids much more frequently.