Preparing to render a small amount of exposed internal brickwork. I've got the sharp sand, cement and Sika Mix Plus Plasticiser . However the cement I've got is Blue Circle Mastercrete. This contains a small amount of lime, and the data sheet suggests that the use of the plasticiser is not necessary. Is this correct. Should I go ahead without the plasticiser, or would I be better off using a more basic cement and adding the plasticiser.