How Long Do I Need Light On?

[Carp4U]

I have a Rekord 70 tank and i think the light is 1WPG and 15 watts and it has a reflector too. If i am to maintain a healthy planted tank with a large but basic selection of easy plants how long should i have the tank light on for?

 

[SuperColey1]

As a guide between 8 and 12 hours. Set it on timer so that it always comes on and goes off the same each day. If you want to go longer than 8 I would suggest starting there and then adding ½hour each week until you reach what you want.

In nature it is 12 hours sun and 12 hours not in the tropics but this is not nature and 8 hours is enough for all plants. longer can mean that existing algae gets even more light sometimes!!!

Andy

 

[Colin_T]

If you have plants like Ambulia and Hygrophilla polysperma, then they close up their top leaves when they have had enough light. Leave the light on for an hour after they do that and the other plants should have had sufficient lighting too.
You can have the lights on for up to 16 hours per day but start off with 8-12 (as suggested by SuperColey) and see how it goes. If you don’t get any algae then you can increase the photoperiod. If you get lots of algae then decrease the lighting time.