Lighting hours

[LarsB]

I'll be getting the plants for my new tank tomorrow and I'm going to start with 6 light hours a day, increasing it to about 8 hours over time.

Now, because I'm sometimes home for short periods throughout the day (college and work), I was wondering if its possible to increase the light hours to 10 hours using a LED dimmer. In that case the lighting scheme would be as follows:
11 am - 12 pm: 20% intensity
12 pm - 1 pm: 50%
1 pm - 7 pm: 100%
7 pm - 8 pm: 50%
8 pm - 9 pm: 20%

The tank will be heavily planted and I'll be using pressurized CO2 with EI ferts dosing.
Would this cause any excessive algae growth?

 

[AndreiD]

I would say 10 hours is too much if you are a beginner , I would stick to maxim 8 hours and see how it goes

 

[Edvet]

I would advise to start with 6 hours.
If all goes well, healthy growth, no algae you can slowly add some ramp up and ramp down, i would add in small increments every 4/6 weeks.
It's far easier to overdo lighting then to get healthy plantgrowth.

 

[Tim Harrison]

There is little point in increasing the photoperiod to more than 9 hrs even when grown in and mature and biologically stable, it tends to encourage algae rather than benefit the plants.
Intensity is often more important, and CO2 flow and distribution paramount. All my scapes have been moderate intensity and the photoperiod is rarely any longer than 6hrs; I can still grow compact carpets.
I suggest that you keep the light at around 3-5% outside the photoperiod. It's light enough to see the critters but dark enough not to trigger photosynthesis and encourage algae.

 

[Tom Michael]

I would advise against long ramping up/ramping down periods for you lighting as this previously caused me algae issues. Stick to 30 mins either end.