"watts per gallon"
 

This standard American measure of lighting presents a problem -
fluorescent lights produce anywhere from 30 to 110 lumens/watt!
I'd like to come up with a metric conversion (it would be
lumen-hours/liter). A survey of what aquarists really use could
help establish that.

So, my question to newsgroup readers who grow plants in fresh
water aquaria is: what type(s) of fluorescent lamps do you use?
To judge lumen output, the type code of the lamp (e.g. F40T12/WW),
manufacturer, and its age (how many hours/day do you run it,
how long has the lamp you have been in use) are the most important.

"watts per gallon"
 

John Sankey wrote:
This standard American measure of lighting presents a problem -
fluorescent lights produce anywhere from 30 to 110 lumens/watt!
I'd like to come up with a metric conversion (it would be
lumen-hours/liter). A survey of what aquarists really use could
help establish that.

So, my question to newsgroup readers who grow plants in fresh
water aquaria is: what type(s) of fluorescent lamps do you use?
To judge lumen output, the type code of the lamp (e.g. F40T12/WW),
manufacturer, and its age (how many hours/day do you run it,
how long has the lamp you have been in use) are the most important.

Try 70-90 lumens(a poor measure of PAR BTW) for most FL's.
10-12 hours is decent for time.

The size of your tank will tell how much you need much more if you feel
you need specific help in that regard.

Regards,
Tom Barr

www.BarrReport.com