Fry Development
The female moved the wrigglers by mouth into the depression that had been dug beside the spawning rock. The wrigglers were tended carefully by the female, for the 4-5 days it took for them to become free-swimming. The male continued to defend the spawning territory, checking on the brood frequently for several seconds at a time. For the brood care period, the yellowish body colour, the black eye stripe and the black lateral blotch of both the male and female, became very intense. The pair continued to feed during the spawning cycle, however, the female would not leave the brood for very long. The fry may be left with the adults, however, the numbers decrease quickly in a community aquarium, as the parents are not particularly efficient at defending the mobile fry. Also, the intake on any power filter should be covered with a sponge that does not restrict the water flow but, pre- vents the mobile fry from being sucked into the filter. To ensure some fry survival, I removed most of the fry, about 90%, soon after they became free-swimming. I placed them in a 40 liter (10 gal.) aquarium, with- out substrate, filtered with a mature sponge filter for the first week or so, then transferred them to a 120 liter (33 gal.) filtered with a sponge filter and a box filter with the lid removed (so it does not trap fry). I did, however, leave the pair in the community aquarium with a few fry to ensure pair bond stability, although, after several days, all those fry had been eaten by the other fish in the aquarium. Rearing the fry presents few problems. They can be started on live, newly hatched , with prepared foods added later as they grow. However, the fry seem sensitive to nitrates, which can cause mortality rates up to 100%. I lost the entire first brood to nitrate toxicity before realizing their sensitivity to it. To prevent further losses due to nitrate, I did a 30-50% water change every other day, combined with regular filter cleanings. This resulted in healthy, fast growing fry from the three subsequent broods the original pair produced. Another rather obvious precaution is to not crowd the fry excessively during the first few months. I used a 120 liter (33 gal.) aquarium for the 80-100 fry per spawn for the first three months or so, then moved them to a 90 cm, 160 liter (3 foot, 40 gal) aquarium to prevent crowding. After several months they begin to show the adult colour pattern, at which time they can be sold or traded to reduce density in the rearing aquarium. The young fish can usually be sexed at about 4 cm (1.6 inches) total length, around 5 months old.
