Don't Look in the Basement (Cue scary music - with bubbles)
Not to obsess but mysteries are for unraveling. There is an appearance of having been "fried" from the skin being separated, wondering if a power surge could have electrocuted them. One would then assume they ended up under the drift either because that's where they instinctively fled when set upon by an invisible assailant (electricity) or because the water current carried them there after they perished. If you decide to start fiddling with your heater be careful —I've never heard of anyone being electrocuted by one but then I've never seen a Nightmare on Cichlid Street either until now.
Love the question about last time you did a water change. Allow me to save someone from embarrassing themselves by asking the classic, "What are your water parameters?", although in fairness it might be worth checking the pH just to eliminate the possibility of some bizarre perfect storm/cascade scenario that turned the water into not so mild acid/base in a matter of hours. Someone who understands physical chemistry better could say whether a mild/strong electric current could produce such an effect.
Just remember, you asked, but for that I give you points. Not sure I'd have been willing to share/profess such a grisly circumstance even with friends ( I do have one or two) let alone the entire aquatic cyber community.
By the way, what species of fish do the acronyms represent? All I could divine from a cursory Google search is that both are otherwise considered "bad boys"...
