i wasn't speaking of meds i meant fertz, i have a working theory that excel also kills many of the mirco-organisms that fliter feeders eat.
your loaches were actually fighting, its really cool to watch, and one of the few territory battles where the fish do no injure each other in the fight.
with all of the bottom dwelling fish you have, i think you need more caves.
i asked about water because petcomarts use tap and if you had R/o that could have been part of the problem, however i guess it is not.
your tank is very warm, mine generally dont feed when it warms up like that. i would cool it down to at least 78. i think that this is your biggest problem. most of the people i know who have success keeping these guys, keep their tanks between 74-78. mine sits between 73-79 depending on the time of day. when the tank is around 79 or up my guys feed less or not at all.
as for the spot feeding, there is nothing in flake food that appeals to filter feeders. its the same thing as when some one puts food infront of you that you don't like, or even recognize as food, they won't eat it. i would try this again with just the algae waffers crushed up and not as a paste, but as a slurry. the zucchini or squash (i have had better luck with zucchini) will not muck up your tank, and is used by many shrimpers for food, otos, and various other bottom feeds will also find it to be a tasty treat. you can safely remove it after a few days, no harm to tank.