Light ATS opposite DT?

[dirtycontour]

Hi all, in the process of building my first ATS. Would my photoperiod be opposite DT or does it matter?

[rleahaines]

The opposite photo period for the scrubber vs. the DT is to help keep your PH stable as photosythesis in the DT in your corals and other critters shuts down during the dark. The actual amout of PH change may not be enough to worry about for your system depending on what you have in it.