how long should i keep aquarium lights
If you have a freshwater planted tank or a reef aquarium most people recommend running your lights for 8-12 hours per day. This should give your plants or corals plenty of time for photosynthesis. No matter what type of tank you have the use of a timer to turn on and off your lights is recommended.
Lighting a saltwater aquarium depends on the type of aquarium you have. If you have a fish-only aquarium, it is recommended to leave the lights on for about 8 to 10 hours a day to simulate the natural cycle of daylight. Any other time period may stress the fish and could lead to unwanted diseases.