Klamath Lake (Oregon) ecology

[A. Pasmur]

Hello,
I wonder: around Klamath Lake in Oregon, several companies make 
tremendous profits (in the hundreds of millions) by harvesting and 
marketing a super blue-green algae (I forget the scientific name).
The companies claim to be environmentally sound and even beneficial, 
But how can this be so?
They extract tremendous quantities of the algae every year.  Does this 
new development in the lake ecosystem -- mass exploitation of the native
algae population by man -- really do no harm at all to the lake's 
system?  What normally happens to the immense biomass of all this algae 
in the lake?  Does it just settle down to the lake's base?  Or are the 
cyanobacteria more likely a fundamental trophic level in the lake, upon 
which countless higher taxa such as fish, invertebrates, and other 
bacteria depend?  If this more likely scenario is the case, then aren't 
Cell Tech and the other companies taking away a fundamental basis of 
life for an entire assortment of inter-related species when they dredge 
up tons of the previously untouched algae for human consumption?
   Or is Klamath Lake a weird example of an ecosystem composed of only 
one permanently renewable species, the super blue-green algae?
What's going on in this lake?  Before I start eating the stuff, I want 
to make sure Cell Tech isn't destroying nature.
Any comments would be IMMEASURABLY appreciated.  Thanks
                                                   A. Pasmur