Posted by Shari Horowitz in Tropical Fish Hobbyist Blog on June 8, 2012 at 11:52 am
By David E. Boruchowitz
Central American lakes like Lake Nicaragua have a unique fascination. Some of our favorite small cichlids live there, as do large predators like the wolf cichlid (Parachromis dovii), not to mention the toothsome crocodilians and full-grown bull sharks on freshwater vacations. You can create a very interesting (if rough-house) biotope community around such a habitat—without the man-eating capabilities.
For this one we’re going to use a 6-foot tank, 18 inches wide, either the 100-gallon or one of the taller versions, like the 125. Substrate is a couple inches of natural gravel, and the bottom is broken up into visual territories with various rock piles, pieces of driftwood, etc. Caves and overhangs are important, since the cichlids we’re going to use are cave-dwelling and territorial. The 9 square feet of bottom area gives us the potential for three territories if all goes well, so make it look like three separate areas divided by rock formations, with the caves separated as wide as possible, preferably with entrances facing in different directions so a fish sitting in the doorway won’t be so tempted to go on border patrol.
Plants are not impossible, but their prognosis is guarded. Tough ones like Java fern, which don’t mind too much if they get shoved out of the way, or hardy Anubias growing on stones or pieces of wood are best. Potted plants might work, but if they cannot uproot them, cichlids often shred plants to make sure they will not harbor ambushing predators. You want powerful filtration, either a canister filter or a couple of large hang-on power filters.
For fish, we’ll choose three pairs of Archocentrus or related cichlids. You can pretty much take your pick from any of them, but if you select a milder species like Cryptoheros spilurus, you probably don’t want to also include bruisers like Rocio octofasciata or exCichlasoma salvini.
A good choice for variety, color, size, and compatibility would be three pairs selected from the following for species: convicts (Cryptoheros nigrofasciatus), blue-eyes (C. spilurus), firemouths (Thorichthys meeki), and flyers (Archocentrus centrarchus). All are readily available, about the same size, and of similar habits. To put some activity in the upper part of the tank, and to give the cichlids a target for their aggression, let’s add eight wild swordtails, three males and five females. If you do not want to go for an accurate wild species like Xiphophorus montezumae, then use green swordtails, which are close to the wild form of X. helleri. A school of a dozen Mexican tetras or their cousins, the blind cave tetras, (Astyanax mexicanus), finishes the stocking.
If you can establish a dynamic peace, your cichlids might even spawn. It is doubtful you will raise any young, but with the tenacious parental attentiveness of these fish, it’s possible!