here's a few observations i have noticed in my experience with black spot:
1) it affects other fish than tropheus. although most often seen with tropheus and gibberosa imports, i have also seen mbuna species, oto. tetrastigma, enantiopus melanogenys, and callochromis arrive with black spot. i am beginning to suspect 'WC' means 'with contamination'
2) both affected females, and females with no apparent markings, can produce fry with it. i believe, that even though the markings are not blatantly obvious on all, if some 'show' it, then most/all fish in that group 'carry' it.
3) an importer once advised me to pick off the affected scales. although the black seemed restricted to scale, and the flesh beneath was clean of it, after a bit of experiment with this procedure, i concluded it best to simply pass over buying them AND buying from that importer. even after ridding the obvious, it continued to return in other/same fish within the group.
4) i have bought/sold 'more than enough' affected colonies, and have never witnessed a cleansing of it, by ANY means. reduction=yes. riddance=nope. it does not seem to be fatal, as many colonies are still around, but no keeper is pleased to own/show them. IMHO, importers need to be embarrassed sufficiently to pressure their exporters for a better cull.
5) there appears to be no market demand to identify, or assist with curing, affected fish. where are the aquarium pharmaceutical companies on this topic?
