Wow, light bulbs are going thru my mind now and I'm stuck in that, "So that's what was happening" facial expression.
Mumma and everyone else who commented, this post has been more helpful to me than the few months of asking the "Pet" store employees questions, I can't thank you all enough.
Ok, Melafix is out of my stash, I'll use the aquaruim salt for treatments only, and this weekend I'm getting a API test kit. Unfortunately the bettas aready residing in my tanks will stay as is(I had areas set out for the set ups), I'll just clean them every other week now. I have 11 bettas all together(10g sectioned w/6 bettas, a 5.5g w/3 bettas, and a 3g w/2 bettas). I check the water parameters weekly w/nitrates/nitrites(0-15), ammonia(0-5), hardness(soft), and ph(6.8-7.2) all at safe levels. Problem is they were checked using the strips, so now I have to retest the levels when I get the API kit. For all I know my ammonia levels could be off the meter.
All of my tanks have surface area for them to breathe air and two of them have filters which I made drip trays to distribute the water and lessen the water turbulence. I realize what cycling is now after the fact and numerous "mysterious" fish deaths, that had me puzzled & stressed. Pet store employees were telling me that I should clean the water more(hence me putting in filters) and add salt. Upon start up I was instructed to add "Stress zyme" and let the tank run empty for 24hrs, that was my cycle,... Shame I know.