🚀 go-pugleaf

	I have a 29 gallon marine aquarium that has a severe problem
with black algae forming on the coral, dolomite, and glass of the tank.
There is an undergravel filter as well as an outside filter.  There
have never been any fish in the tank, only invertebrates, and it has
never been particularly crowded.  The water always tests well within
limits on ph, etc.  People in pet stores have had some suggestions, none
of which have worked.  These included trying different lights and getting
animals that will go around eating the algae.  Any suggestions?  There
is currently 1 20 watt fluorescent bulb in the fixture - there does not
seem to be a fixture made that would take 2 20 watt bulbs and would still
fit a 29 gallon tank.

	Another question:  What is the best type of air pump to run
an under gravel filter?  I have an old Hush pump which is no longer made
and the parts necessary for routine maintenance are no longer available, at
least in the Boston area.  I am particularly interested in ones that
will run quietly, as the constant vibration of some can get on your
nerves after a while.