[Myka]

Alkalinity 70 (kit I use to measure says it should be around 100)
Should be closer to 140-160 ppm imo.

Calcium 450 (kit I use to measure says it should be around 450)
Should be 380-430 ppm imo.

Fish (and other things) that have died:
Copperband - nothing noticably wrong had for 5 months
This is typical of CBBs. They do not generally do well in captivity long-term.
Flame Hawk - jumped after 1 day
Many fish will jump when first acclimated or anytime when chased or startled. In the ocean they can't fall out, so jumping is quite natural for many fish as a way to avoid predators or catch food, etc.
Red Scooter - didn't look skinning or anything had for 3 months
Did you ever see him eat prepared foods? If he was in there at the same time as the Mandarin there would be food competition. I would guess he starved even if you didn't think he looked skinny.
Potter's Angel - nothing wrong had for 2 months
Possibly worms or flukes. That's about the right time span. Did you ever see him rubbing or flashing on anything?
Lawnmower Bleeny - nothing noticably wrong had for 1 month
Starvation? They eat LOTS of algae and don't usually eat prepared foods.
Madarin Goby - nothing wrong had for a year and a half
Kinda weird if you had him that long.
Sohal Tang - didn't really eat too much had for 2 months
Sounds like starvation.
Bar Goby, Flasher Wrasse and Firefish- jumped after a number of months
See Flamehawk.
Cleaner Shrimp - nothing wrong had for 2 years
Kinda weird too. Sometimes they get stuck in their molt though, and will die. Iodine plays a part in their molting...too much or too little, both are bad.

Hope that enough info... I know they're not all perfect but again, if the corals are doing well shouldn't the fish be fine since they're hardier????
I find most corals hardier than most fish.