Well depends on the tank, I have some tanks with ohh around 800-1000 shrimp in them... SO those a bunch
My PBL tanks has 17 in it and I feed 2 smaller spinach leaves when i blanch them, if I am doing squash or Zucchini I do half a round cut in half about 1/4 thick. Blood worms I feed almost a half cube. Butter nut squash I feed 3 squares about the size of my pink finger nail. kale about the same as spinach, peter laidens food 4 small pellets.
No wonder my shrimps ganged up on the ramhorn. I have been too stingy on feeding blood worm. I also feed blood worm once a week but only 6-7 worms for the tank of 18 PRL and the babies...
Do you leave the food for an hour or until they clear it up? I always hesitate taking food out after 2 hours because all the shrimps are still fighting for it.