How Long Should I Have The Light On For?

[PennyHardie]

My tank is near a window but out of direct sunlight. It had a light also. How long should the light be switched on for each day? If it is on for too long do I stress the fish?

 

[Akasha72]

do you have natural plants in the tank? If so they'll need around 8 hours of light for them to thrive. Too much light and algae could take over, too little and the plants will die. 
If your not around to switch the lights on for that length of time then you could always get a timer from the diy store that will switch them on and off for you