Captive Care Notes: Satinfin Shiners (Cyprinella, Family Cyprinidae)
Cyprinella are fast, athletic swimmers that make seemingly impossible moves at high speed, sometimes chasing each other in circles so tight you can't tell one fish from the other. Such athleticism makes them a joy to keep in the aquarium even if they don't color up. Surprisingly, though, male Cyprinella often retain their nuptial colors in captivity, especially if the water is kept around 21C (70F). Most species are peaceful and unassuming, although male satinfin shiner can be quite territorial and may unmercifully chase any fish that can't get out of their way. For this reason do not keep single specimens in community aquaria. Instead, be sure to have three or more specimens in order to more evenly distribute aggression and maintain at least a semblance of peace between species.
Cyprinella are undemanding in aquaria, except maybe for burning more energy and therefore requiring more food than slower-moving minnows. Fortunately, this is not a problem since Cyprinella will eat almost anything offered. With ample diet, sufficient water quality, and a suitable place to deposit their eggs, Cyprinella should reward even the most lackadaisical fishkeeper with a spawning or two.
Cyprinella are "crevice spawners" that deposit their eggs in submerged logs, loose bark on fallen trees, tree roots, and other woody debris, or in the cracks between rocks and boulders. In captivity, artificial spawning crevices can be constructed out of two terra cotta tiles stacked one on top the other. Separate the tiles with a piece of felt or a few silicone beads, and offset them so that the bottom tiles protrudes a centimeter or so. Studies have determined that a 3 mm-high crevice is preferred by Red Shiner (C. lutrensis) and Bannerfin Shiner (C. leedsi) over other heights. Master aquarist Robert J. Goldstein reports four species (lutrensis, nivea, pyrrhomelas and venusta) spawning between the pleats of Magnum canister filter cartridges. After spawning, move the filter cartridge to a wide-mouth glass jar with vigorous aeration. Newly hatched Fieryblack Shiner (C. pyrrhomelas) fry are large enough to take brine shrimp nauplii; other species require smaller food items such as rotifers, infusoria, and green water for the first two or three weeks. Fry can start taking powdered flake food at half an inch, and whole flakes at one inch.
Red Shiner will spawn in just about anything: green acrylic yarn (simulating a bed of plants) anchored on the aquarium bottom, Java moss, and in artificial gravel piles constructed out of variously sized glass marbles. If you use a non-creviced spawning medium, be sure to remove the parents after spawning as they will eat the eggs. Red Shiner will spawn in captivity as frequently as every 48-72 hours. Spawning occurs most often in the early morning, almost immediately after the aquarium lights are switched on. Gale (1986) hypothesizes that if the lights are never turned off, sexually mature red shiner will continuously produce eggs and spawn until they die.
Bannerfin Shiner spawned in 20-gallon "high" aquaria maintained at 22-26C (72-79F) with undergravel filtration and 16 hours of light and 8 hours of dark; the fish were fed commercial flake food. Spawning occurred in between 15 x 15 cm (6 x 6 in) clay tiles as described above. Blacktail Shiner (C. venusta) spawned on tiles in a 208-liter (55 gal) aquarium on an identical light cycle at about 24C (75F). The addition of current may also facilitate spawning. Steelcolor Shiner (C. whipplei) and Spotfin Shiner (C. spiloptera)), kept over the winter and fed a variety of live foods and frozen brine shrimp, spawned on a slab of rough bark in March when water temperature reached 21-24C (70-75F). Lucas (1991) witnessed mock solo spawning among Spotfin Shiner in a 30-gallon community tank: "... the male would often swim in front of her [the female], rubbing his belly in a crevice as if to demonstrate his intentions." Eventually a female would squeeze her ovipositor into a crack or hole, but, interestingly, not always the one the male had pointed out. Lucas' well-detailed account, published in the NANFA publication American Currents, demonstrates that amateur aquarists can make keen-eyed natural history observations from the comfort of their living rooms.