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Lightbulbs and blue-green algae experiences

Tim Ayers mentioned:
In two other 10 gallon tanks I tested the notion of "If you have
enough light, the quality doesn't matter as much." I have incandescent
strips for these tanks and I found GE 13W compact fluorescent bulbs
with incandescent base at Wal-Mart for $5/ea. These bulbs are 2700K
color temp. <snipped list of plants> After a
couple months with these bulbs the blue-green algae has taken over
both tanks.

Things to consider before concluding that the spectral power
distribution of the lamp is causing the algae:
1) The color temp of most common compact fluorescent lamps are meant to
closely approximate that of the incandescents they're meant to replace.

2) The CRI of the compact fluorescent will probably be a little lower
than that of the incandescent.  Incandescents usually have a CRI of
around 100.
3) The thermal temp. of the fluorescent is a lot lower, assuming you
replaced the incandescent lamps with compact fluorescents that have
about the same lumen output.  In your case, that would be about a 40W
incandescent.  So if your incandescents were over 40W each, you now have
less light in terms of lumens.

I wish we could get GE compact fluorescents with replaceable lamps for
$5.  Heck, that's cheap even for the throwaway no-name ones.

Good luck,
Wade Shimoda