Glenda, the Corid liquid I use is the 9.6% solution. Costs me about $20 for 16 ounces. It's not easy to find around here, but First State Vet supply right now has a special on the powdered Corid, which may be a good deal.
5 cc's- 1 tsp
10 cc = 2 tsp. so, I'd say that a teaspoon and a half...
I am adding something to this Corid vs Sulmet discussion. Sulmet is NOT effective against one of the nine types of cocci, the one known as eimeria tenella. That type sets in between 4-8 weeks most often and does cause intestinal bleeding, more so than other types, some say. Sulmet won't touch...