Cells with values

I have this code to replace any blank cells in column C with the phrase "in composite"
[VBA]Sub ZerosAndBlanks()
' Fill zero and blank cells
Dim cll As Range, rng As Range
Set rng = Range("C1:C" & Cells(Rows.Count, "C").End(xlUp).Row)
For Each cll In rng
If cll.Value = "" Then cll.Value = "In composite"
Next cll

End Sub[/VBA]

I would also like to have a code to replace any cell in column C that DOES have something in it with the phrase "out of composite"

What do I need to put for ??? to trigger all cells that contain something?
If cll.Value = ???? Then cll.Value = "out of composite"

[VBA]Sub ZerosAndBlanks()
' Fill zero and blank cells
Dim cll As Range, rng As Range, rngB As Range
Set rng = Range(Cells(1, 3), Cells(Rows.Count, 3).End(xlUp))
Set rngB = rng.SpecialCells(xlCellTypeBlanks)
rng.Value = "out of composite"
rngB.Value = "in composite"

End Sub
[/VBA]

It says there is an error with this line, error saying no cells were found

Set rngB = rng.SpecialCells(xlCellTypeBlanks)

There must be no blank cells. Can you post sample data?

thanks for the help, this works great!