"SG" wrote in message
...
In article , NetMax
wrote:

I think you are in r.a.f.p. more than I am these days, but the number
I
hear repeated a lot, is to keep below 3 w/g unless you are using CO2
injection, otherwise you risk making green soup out of your freshwater
aquarium.

Interesting. I may get that CO2 injector for the new tank after all.

Full noon tropical sunlight is about 10000 (10k)
lumens/square_foot. About equivalent to 110-125watts/square_foot of
high intensity flourescent (VHO, power compact) or metal halide. By a
rough measure as sunlight has a much better spectrum then man made
light.

Interesting data, so my 60g would receive 6 sq.ft. x 120w at high noon
(equivalent to 720w or 12w/g). I wonder how far from noon the sun has to
be for refraction to significantly reduce light penetration. The
tropical sun is on more than the daily typical 12 hours of light we use,
but our lights are full on instead of peaking at high noon, and we don't
have to content with cloudy days. In my 2.7 w/g setup, there is 160w or
1,920w/day. I wonder what a tropical exposure would be after allowing
for refraction & cloud cover. I bet it would still be more than
1,920w/day. I might have this in my notes for solar radiation by
latitude, but to find it *&#!. Anyone have this figure handy? It's
commonly used for solar panel configurations.

NetMax