You don't need CaCl2 for fromage blanc. If the curd is weak, then:
- Milk solids possibly low
- possibly not enough rennet used
- culture blend is off for the temp, or temp schedule does not match culture selection (should be 75-78F)
Wait a few more hours, but I doubt it will make a difference. If it doesn't drain well, heat it up, that will firm it up some, but will not give you as smooth of a texture