Hello Shark...
Sex reversal can happen with Livebearers. Sometimes conditions are right for these fish to develope characteristics of the opposite sex. I've kept Fancy Guppies for about 10 years and sometimes had a male that's extremely large and have little or no color. it has something to do with the fry having the potential to become either sex. It depends on which type of "plumbing" grows quicker. It's been my experience that they live a long time, but are sterile. Just a little "hiccup" in nature.
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