I agree that the culprit was most likely residue of chemicals from the painting and other work that was going on in the new home,as he suspected.....either way awesome " L"shaped tank and collection with nice big ST's.I am wondering if his arro died from new home syndrome or the calming drug he used to transport the fish.
Yea. I don't think its nesessary to sedate a fish to move. But also look how many fish were jammed into that tank. The filter probably went nuts. All kinds of ammonia and nitrate spikes.