Lighting Question

[wet44]

Hey all, I recently got a light with a white light setting and a blue light setting. You can hook both of them up to a timer. I currently have the white light set for 7 hours and the blue light set for 9 hours (one extra hour on each side of the white light time)
 
Does anyone have suggestions for the most light I can get out of it? Would it hurt to leave the blue on all the time?
 
Thanks!

 

[hudsona85]

Is there a reason as to why you would want to keep them on? Excess light will cause algae growth and disturb the fish sleep cycle.

 

[Byron]

If by "leave the blue on all the time" you mean 24/7...this will absolutely cause real issues for the fish, and the plants.  Both must have a period of complete darkness.  But if you actually mean leaving the blue on with the white during the 7 hours...maybe.  It depends upon the intensity and the plants.
 
I tried a LED unit for about two weeks, and it had separate blue lights which I never used on their own.  These will be insufficient to drive photosynthesis which means the plants cannot make use of the light, so algae will take the advantage.  I would suggest reducing the blue light from one hour to half an hour before and after the white light period; this is sufficient for a gradual light increase/decrease for the fish (like dawn and dusk) and less likely to increase algae, though it might still do this.
 
Byron.

 

[wet44]

Thanks for the advice. It's just a Marineland LED strip. I have rotala indica, java fern, anubias, a small crypt, and a dwarf lily plant. They are all mid to low light plants I believe.  
 
I will change the blues to just be half an hour before and after the whites and see how that goes. Not sure why I thought having the blue on the whole time would be a good idea; I now realize that that is a terrible idea, ha.