University of Maryland biologists have genetically mapped the sex chromosomes of several species of cichlid (pronounced "sick-lid") fish from Lake Malawi, East Africa, and identified a mechanism by which new sex chromosomes ...
Tropical Fish for Freshwater Aquariums: Butterikoferi African Cichlid
Another good choice is Java moss (Vesicularia dubyana), which will also attach to driftwood, and the old standby, water sprite (Ceratopteris thalictroides), which, although plantable, is better used as a floating plant. Water sprite grows fast and covers the surface, cutting down on the intense surface illumination — again, useful in making cichlid fish feel more secure.
Cichlid Fish Information - Petcha
Caves are also used by prey trying to escape its predators; since the victims can be any size, you need many sizes of caves. Submissive males will also use caves to escape the harassing of dominant male cichlids, while carrying females, as well as sick, or wounded fish will use them as a shelter. Finally, ground-floor caves are often used as day homes for nocturnal species like catfishes, plecos, loaches and Synodontis species.
Golden Severum, Heros severus, Banded Cichlid Fish Guide
To determine whether males produced sounds during typical courtship behaviors (e.g., body quivers, leading, tail waggles, pot entries), we placed a single dominant reproductively active male in the center compartment of an experimental tank (48×165×30 cm) along with three females and a single terra cotta pot to serve as a territory. This central compartment (48×30 cm) was bordered on either side by larger community tanks that contained fish of both sexes and various reproductive states so that the subject male could interact visually, but not physically, with his neighbors across a clear acrylic barrier. The subject male (N = 22 males total) was allowed to establish a territory and acclimate for 24 hrs prior to sound recordings. To examine possible relationships between sound characters and male body size, we also used dominant males that ranged in size from 47–87 mm standard length. These dominant males were selected from community tanks where they were verified to hold a territory and perform typical dominance behaviors , for 3–4 wks prior to testing.Astatotilapia burtoni was most sensitive to low frequencies from ∼200–600 Hz, with a best frequency at 200–300 Hz, which overlaps the spectral content of the courtship sounds produced by dominant males. While many studies have described sound production and associated behaviors in different cichlids , , , , , , , , , , , , , , hearing abilities have been examined in only a few species (e.g., Tramitichromis intermedius, Astronotus ocellatus, , Tilapia macrocephala, , Neolamprologus brichardi, and Oreochromis niloticus). Further, the majority of these studies only tested the cichlid species as an example of a fish that does not possess specialized auditory structures (e.g., Weberian ossicles), for comparison to those that do (e.g., goldfish), rather than specifically to examine the biological significance of their hearing abilities. In fact, aside from N. brichardi being used as a goldfish comparison , ours is the first study, to our knowledge, to describe hearing abilities in any cichlid from Lake Tanganyika. As a result, little is known about how sound production is matched to hearing abilities in cichlid fishes, but along with the present study, there is evidence for this matching of low frequency sound production and hearing ability in T. intermedius and Oreochromis species , , , which highlights the potential importance of acoustic signaling in cichlid communication. However, it is also relevant to mention that exact matches in spectral content between hearing ability and sound production are not required for effective acoustic communication, as many sound-producing fishes show only weak correlations between best frequencies of hearing and dominant frequencies of sound production , . This may be partially due to the fact that many fishes produce broad band sounds that contain multiple frequency components, so that sensitivity to a pure tone stimulus can be worse than to a multi-frequency complex sound with equal peak intensity but more total energy within a critical hearing band , . Thus, the selective pressures acting on both hearing ability and sound production within a species are complex and deserve future study before generalizations on these aspects of acoustic communication among different taxonomic groups of fishes can be made.