John,
I found that my macros grow under just about ANY lighting. I have C. Serrulata and Chaetomorpha that is growing in a 10 gallon tank with a standard AGA plastic hood and the silly little 15W bulb that comes with it. I have no idea what spectrum that is, but it is pretty "white". I also have it growing in my 26 Bowfront under 110W of mixed full spectrum and
actinic. (55W actinic03 and 55W full spectrum) In my
Sump-zilla, it is growing under a 65W Lights of America fixture at 6500K. Chaeto grows well for me under this same lighting.
I think 65K is just fine for growing plants and
macro algae. It is real yellow/green and not very pleasing light to the eye (my eye anyway) but in a
sump or
fuge...who cares? As long as it is growing right?
Reverse
photo period is simple and looks like this on paper:
10:00 AM - Display lights on*
10:00
PM - Display lights go off
10:00
PM -
Refugium lights turn on
10:00 AM -
Refugium lights turn off
*Some folks have their display lighting such that
actinic lighting comes on first, then
MH..and at the end,
MH shuts off first, and an hour or so later,
actinics shut off. Whatever works for you, or whatever your system is built to do. My display does NOT have independent switching for
MH and
Actinic. My old reef did.
In this scenario, SOME part of your system is illuminated 24/7. This keeps the
pH swings to a bare minimum.
During the "light phase" when macro is using the light to photosynthesize, the macro uses CO2 and in the end, creates a byproduct...Oxygen. This is a good thing. However, the decrease in CO2 and related increase in O2 means and increase in
pH. This level in your system during the "Day" is, or should be, in and around 8.2 correct? This is what you check against with your kits. However, during the dark phase, the opposite happens. CO2 is expelled and O2 is consumed. This causes a drop in the
pH. Test your system in the middle of the day, and again well after the lights have shut off, and you will see the difference yourself.
By keeping a second "chamber" that is lit opposite of that within your display, you are in essence, creating a system whereby one part of the cycle is happening in area A, while the second is occurring in section B. This creates a "wash" of sorts where the
pH should remain constant throughout the system.
Does any of this make sense to you? I'm kind of just regurgitating what I think I know
Here..this will really confuse us
6H2O + 6 CO2 + energy --> C6H12O6 + O2
Dave
