Sorry the fish died; this is an expensive hobby no doubt. I remember in the days of lfs in SF having the same no gaurantee on fish when it left the store in 70's and I would find it strange if a store did have a guarantee to be honest.
I have shopped at AC before and never had a problem.
Ball Pythons have such interesting morphs. I think I spent several hours perusing this site http://www.worldofballpythons.com/morphs/ and few other breeders websites.
More of the so called actinic range in the old school T-5 and/or PC bulbs. I had the lighting setup as 20k, actinic, and a little bit of 14k in the bulb array. As far as metal halides - aqua connects & radiums also gave a bit of coralline growth.