Sometimes simple is better. This worked for me.

Dim FreeSpace As Double
For Each r As Infragistics.Web.UI.GridControls.GridRecord In DiskSpaceWebDataGrid.Rows
   Dim FreeSpaceCell As Infragistics.Web.UI.GridControls.GridRecordItem = r.Items.FindItemByKey("FreeSpace")
   FreeSpace = FreeSpaceCell.Value
   If FreeSpace < 8 Then
       FreeSpaceCell.Text = "<font color=red>" & FreeSpaceCell.Text & "</font>"
   End If
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