Because... well I obviously can't say for sure, but my closest guess is that they are some amazing colored Protomelas taeniolatus... ie red empress. But that is way too young for that color. I would at least strongly lean on Protomelas of some sort. Now I do realize it has vertical bars and no real showing horizontal strip, but as you said they are stressed and those change depending. But I would lean towards the tangerine tiger??? Just a guess... since don't see the horizontal and don't see purple at the moment, else maybe red empress, Again at least fairly sure a Protomelas.
Do a google search for some good examples. (Just of tangerine tiger)