How long should my light be on?

[Tim]

Just curious how long my lights should be on for during the day.
I have a planted tank.

Thanks

[dpatte]

12 hours

[BigDaddy]

The only time you would modify that is if you had an algae outbreak.  Then, you sometimes may want to drop the photoperiod down to 8 or 10 hours until things are back in order again.

[TBarb]

Does daylight come into effect in calculating total time? (in addition to the time the lights are on)

[dpatte]

i run my lights from 8AM to 8PM

[adamarchibald]

i also run 12hs