On Wed, 01 Jun 2005 09:53:30 -0300, Derek Broughton
wrote:

UVs
they're very efficient, but imo not a good idea. When you have an algae
problem, it means you have too much nitrate, phosphate or light. Sometimes
it means you have nitrate that can't be used by vascular plants because
they don't have enough of something else (frequently potassium).

Or the pH is too high or low that the plants can't take up the
nitrate. ~ jan

~Power to the Porg, Flow On!~