
Back in the late 80s, I had a pair of managuense that would spawn regularly, and in each spawn there would always be a half dozen or so fry that would be gold in color, but at the juvies aged, the normal color siblings would tend to cannibalized by the gold ones.
I separated afew gold ones and grew them out sepatatly and they survived, but I found the solid color morphs boring so gave them away.
I believe the adaptation is a survival tactic in some genes, in case some event in geography changed topography, that made the normal coloring stand out to predarores, and in order to preserve the species, that gold adaptaton might ensure survival.
There were also many aquarists that would turn in large individuals to LFSs when they got too big for their tanks.
Maybe these days , aquaristss maintain larger tanks, so can keep large individuals longer?
Maybe the just eat them?
Maybe some aquarist are wisening up, and not buying fish that are known to get too big for the average tanks?
In the past there were many importers such as COA or Tangled up in Cichlids, or Don Konkel, that used to bring in large species, but many of these have retired, or gone out of business, had hurricanes destroy their facitlies, or simply don´t import large species that are hard to sell anymore.
I moved to Panama to collect the cichlid and other species want myself.

