How to set up a loop

I am trying to set up a macro to delete empty rows I have tryed a few things but this is the only code which seems to actully run through it.

How do I set up a loop so it will start at C20 for example and work up the sheet till C2

If ActiveSheet.Range("c20") = "" Then
     ActiveSheet.Rows("20:20").Select
    Selection.Delete Shift:=xlUp
End If