Thanks for the response...I've never really had a clear answer on that one!
I already have 10 hrs now, and no sense wasting light and giving more to
algae spores.

Dave

wrote in message
oups.com...
Many plants close up after a peroid of about 7-10 hours, so they are
not needing any more obviously.

So I stick with 10-11hours.

The other benefit: less heat in the summer, less electric bills all
year, less bulb burn outs/changes etc.

Timers are rather simple devices and folks can use them to set the
times they are around their tanks.

Regards,
Tom Barr

www.BarrReport.com