Aquarium Lighting Needs

Plants need a definite daily light and dark cycle each day. 10-14 hours is fine. You should buy a timer for $5-$10 to automatically turn the lights on and off for you, since the plants and fish prefer a regular cycle. If the plants need more light, you should not extend the light period, as that will only increase algal growth. Rather, install another fixture and increase the intensity of light.