Heeyy all! I'm back! Been keeping up my fishy habbit. Just not frequent on here

ANYHOOS!
Personal News (long story short):
(As you knew) dumped the bf of 3 years, dated a guy who evidently didn't send the memo it was an open relationship after a year, kept low for a few months and now found a Rough Stock Bull Fighter (rodeo guy) and I'm ENGAGED! (Pics later

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For our anniversary he bought me a 55 gallon tank with 2 breeder electric blue Cichlids, along with a Convict Cichlid (named DUI *pronounced Dewey*), a itty bitty Green Terror (named Tweaker), 2 Oscars (one Nigel - black and orange, the other Cracker - albino) and 2 plecos, one Rubber Nosed and one Sail Fin (named CIA and FBI)
Not everyones going in the same tank. The Oscars are getting Mikey's 50 gal. And the cichlids are all going in the 55. Plenty of room and hiding places for all
Anyways, had an issue come up. We initially bought the tank from Craigslist, whom the previous owners kept turtles in it and they *told* us they used vinegar to clean the calcium rings off BUT I have a casualty. The male electric blue passed away on me, and come to find out we called the tanks previous owners to verify they only used vinegar to clean it. Nope. They used AMMONIA.
I can't help but feel guilty, but I wiped out the entire tank with only hot water and a clean wash rag and the water was conditioned before everyone got acclimated, I just didn't use vinegar to cover all my bases
Thoughts? Ideas? Butt chewing?? Lol MISSED YOU GUYS!