I cut the shrimps in half and gut the black lining out then wash it before chopping it up to feed. I usually feed 8-10 which is comes out to be like 1/2 a shrimp to each bichir. Sorry to hear your lost. Maybe reduce feeding and watch for any sign of stress on the fish.
I feel your pain, especially this morning. Sorry about your loss - I've never lost a fish to bloat. The only thing I can think of is that I really don't feed that often. The babies get a lotta food when they should, but the adults? They usually only eat twice a week. I never feed until the bumps in their bellies from their previous feeding have gone down. I still get decent growth rates, and because the fish are hungrier @ feeding time, all the food is eaten with a smaller chance of food getting left in the tank.
Man, losing fish effin sucks. Why can't they live forever????
Let's go to the bar n have some drinks for our fallen friends, shall we??
Do you use feeders at all ?
Some of the shrimp being sold sometimes contain high levels of preservatives to keep them from going bad. May be harmless to humans, not sure about fish though.