dunno what they were thinking when they imported a bunch of these, but they're completely and utterly UNsuitable for captivity!
unless you don't mind "feeding" live hosts that will be scraped and nipped to death.
I once took a stray 1,5" Ochmacanthus home (it was a contaminant in a shipment of non-parasitic Trichomycteridae or so) and it terrorized every other fish in my tank, ranging from small Eutropiellus to the 1-foot Pterodoras!
In the end, I had to euthanize it; it couldn't be fed properly and my other fish weren't exactly happy with the company.....
That was because I made the -wrong!- assumption that a nicely colored fish couldn't be a parasite; I expected parasitic fish to look all "glasslike" like Vandellia and Tridensimilis do.