Algae

["William E. Davies" <WEDavies at nni_com>]

I have an algae problem.  It's blue-gray green and sort of furry.  It
edges the leaves and coats the stems.  Nothing has been killed by it.
The tank is my 50g 36x18x18 with four 30w tubes for light.  The
filtration is a trickle unit, drip plate and bio ball type plus a Hagen
Aquaclear 150.  As with all my tanks it has CO2.  I was adding Flourish
Iron however I stopped when this started.  The CO2 is cut back to
1/bps.  Suggestions please.  As usual Thank You.