Volitan vs. Dwarf???

[geniussix]

my little brother got a dwarf lion (small-Medium) the other week to go along with this Volitan lion(medium-Large).. but in about a week or so the dwarf ended up dying. was that a bad mixture? the guy at the store said theyll be ok together as long as i dont forget to feed them. PLEASE HELP!!!

 

[geniussix]

my tank size is a 55 gallon glass. my salt level was about 1.024. the dwarf was eating frozen krill with kent marines garlic extreme and zoe. it was somewhat leaning on its side just a tiny bit, on the gravel bed i mean.. was it just a overall bad batch that the LFS had?