Id said that wasn't possible until i watched those videos and seen it for myself. I'm fairly certain that the electric blue acara is an andinoacara pulcher and a mikrogeophagus (electric blue ram) that was created by man. If it can be created in a lab I can't see why there couldn't be these ultra rare occasions like this. Very neat is true
I'm convinced the electric blue acara was just the result of line breeding, as the electric blue ram itself just came from line breeding normal rams. Fish that have that natural blue pearling are able to randomly produce fully blue individuals. Thai silk flowerhorns are made by breeding flowerhorns descended from herichthys with high pearling over a few generations until fully blue ones pop up. I don't think the genetics of it have been looked into but I'd like to believe it's some sort of incomplete/codominant kind of thing. Electric blue rams, blue diamond discus, thai silk flowerhorns, and turquoise jewels to an extent, are all good examples of this. EBJD also appear without hybridizing, but if I recall correctly their coloration is based on a recessive gene. Meanwhile when EB rams/BD discus/TS FH are bred to other members of their "species" their colors combine, again leading to me believing they're the result of an incomplete/codominant gene. However, that in mind, the electric blue gene in EB acaras is recessive, as when crossed to normal colored individuals the gene does not appear until those individuals produce offspring of their own. In the off chance that they are the result of a cross to electric blue rams, the gene would then be incomplete/codominant, leading to me believing it is more of an EBJD type case, where a recessive gene randomly popped up somewhere in breeding normally colored, if not abnormally highly blue (but not electric) blue acaras.
Quite the possibility with the eb acara. Considering it doesn't appear to get as large as the traditional blue acara. Line bred until they produce all blue when breeding two EB together.
I have seen 7-8 inch electric blue acaras. Not often, but I have seen them. Again with the EBJD thing, I myself am unsure why but I know they're naturally weaker and prone to dying at a young age, so I would imagine with EB acaras it's similar in that they don't usually reach their full size before dying, leading to people believing their max size is much smaller than what it really is, especially since not much is known about them already. Combine that with the fact that acaras already grow very slow.