[Walter]

Hi,
der Bericht kommt im Welsatlas Bd. 2. Johannes Leuenberger ist der Züchter.
Vires soll ja auch schon Baryancistrus vermehrt haben.
Da die Frage ja immer wieder kommt, hier die betreffenden Passagen aus "Loricariidae - the Tricks of the Trade", von Larry Vires, Vires Publishing 1999:


Baryancistrus sp. "Gold Nugget"
There are several fish which are shipped with this name and it is not uncommon to see some variation with fish of the same species. The true gold nugget is L 18. However, it is not uncommon to find L 177, from a different locality, and several other types which have not been given an L number yet. For this reason, prospective breeders should be heavily scrutinized, not only to allow success, but also to prevent possible hybrids from entrance to the hobby. These fish are all marked with a black body, large yellow spots, and a yellow seam on the distal portion of the dorsal and
caudal fins.

The information given from this point also applies to L 81, spot gold nugget, which can be noticed by the small white speckling rather than the larger spots. The only difference in the care of the 2 species is the required tank size. This is done because L 81 can reach a size of 7 inches, whereas L 18 can reach sizes over 1 foot. The respective spawning sizes are 4 inches and 6 inches.

All of the water chemistry parameters are the same as for any other species mentioned from this area (see the section on Hypancistrus zebra). The nutritional requirements are also very similar, but these fishes have ravenous appetites when properly cared for. For this reason it is important to overfeed them every night and clean the tank every day if success is to be had with spawning them.

Dimorphism is difficult to notice unless the breeders are at full breeding size. Probably the easiest way to sex these fishes is by the shape of their foreheads. Males have flatter, more leveled slope to their foreheads and are slightly wider. Females have a more rounded forehead and are slightly plumper when in spawning condition. There is no notable difference in the odontodal growth in either species.

After having spawned this species off and on for nearly 3 years, I had not found the requirement which would make it possible to easily duplicate the success until late last year. Each time, in the past, the fish would dig caves under the same piece of slate-mounted driftwood and spawn in my Hypancistrus zebra grow-out tank. Whenever the pair was moved to another tank to attempt a spawning, nothing ever resulted from the effort. This is where my theory about the effect of currents came in.

When setting up a new tank system, in an attempt to produce commercial numbers of several species, I intentionally oversized the pump to guarantee a good oxygen supply for all the fishes in the system. However, I had to find a place for my breeders while I made the spray bars for the tanks and the fish were left overnight with only a direct flow from the water inlet. The next morning, upon inspection to see if everyone survived what I thought would be stressful conditions, I found a cluster of eggs laid in the bottom of the tank in front of a rock. From that point on, convincing these fish to spawn has not been that difficult. Once a pair of fish is conditioned and have found a suitable spawning site, the addition of a supplemental powerhead aimed at the cave is all that is required.

Raising the fry is not very difficult, but this is a long process. They will not reach beyond 2 inches within 6 months of age. Feedings should be given regularly with baby brine shrimp initially and the food size increased as the fly gain some size.