Yup. More light for less time discourages algae with no ill effect on plants even below 8 hours. However, if you have WAY too much light as you say you can cut intensity (say by blocking some % of the light with tape or window screen) and then you can extend to 12hours. Too much light is an easy fix. Too little light plus too long a photoperiod as an attempted fix just grows algae.
Last edited by Gold Finger; 11-18-2012 at 01:24 AM.