OK
Don't know if anyone remembers but besides my issues with my oscar burning hirself on hir tank heater (s/he's healing up fine btw

) I've recently had troubles with horrid cloudiness and ammonia spikes with every water change which is bad because most people do water changes to reduce such chemicals.
After doing a lot of research, talking to my independent LFS owner (who is a knowledgeable guy) here's what I've discovered and what I did about it.
Turns out over time out local water supply has been contaminated by ammonia (and other nasties) due to the increased actions of industrial hog lots and inappropriate disposal of waste, which is really sad since our area has enjoyed one of the best underground aquafers in the midwest. So now our local waterworks has to add scary amounts of chloramine to the water.
Apparently my previous loyalties to API's Tap Water Conditioner + Ammolock have lost their rational foundations because those treatments have become ineffective (or at least not effective enough to keep my fish safe and healthy).
This morning, after just having done a water change last night, I woke to find my oscar in dire straits likely due to high ammonia and nitrite levels (the latter caused by my functioning biological filter trying to keep up I'm sure). I changed all of the water and replaced it with water treated with newly purchased Prime.
Long story short, the tank has recovered, the oscar has recovered, everything's A OK again.
Prime ROCKS!!!