Simulation of Dawn-to-Dusk

[aquarius]

I'm thinking of simulating a dawn-to-dusk lighting using two timers for 2 sets of 2x36watts PL lights and was wondering has any body done that for their planted tanks?

This is what i intend to do : Photo period of 11hrs
1st hr, 1 set of lights will come on with the 2nd set turned on at the 2nd hr.
On the 10th hr,1 set will be turned off followed by the other set on the 11th hr.

Will plant growth be better assuming all things are equal/the same and will algae be better controlled using this method?

Would like to hear your views or experiences with regards to this issue.

[juggler]

I have done that before (even now) and found that it is not the solution for algae-free tank. Either with or without the staggered lighting period, the plants can grow well and algae-free if you take care of the nutrient control.

At best, the staggered lighting will not make the fish go into distress at a sudden darkness.

[Johnc]

I do the same. One other advantage apart from not stressing the fishes is that the lower light prepare the plants for the high light. The point is plants go through a 'sleep-wake' cycle pretty much like the creatures. While they are 'sleeping' they do not photosynthesize, and will often be closed up (look at the stem plants at night after the lights go off). In a sense, therefore, the gradual increase in lighting is less 'stressful' for the plants too.

/John

[aquarius]

So i c.... i guess i can also add that (correct me if i'm wrong) you will also safe electricity cos not all the lights are turned on at the same time for the 10 or 11hr period.

[anttz]

Do you inject CO2 on the 1st light-on or 2nd light-on? And do you switch off your CO2 on the 1st light-off or the 2nd light-off?

[Johnc]

If you are using a solenoid, turn on at first light, turn off when high light goes off.