How Does Lighting Affect Chemistry?

[ErehwoN]

I'm hoping this is a relatively simple question without too many "it depends" answers. I'm upgrading my lights to something more powerful, as in as much as 3x. I have a PAR meter and have mapped out the tank and will match the PAR of the new lights to the current setup. I know it's a slow transition from current PAR levels to desired levels and will do that over weeks/months to properly acclimate the tank so things can adjust. So the question:

If we consider all things equal except for PAR, will the increase in PAR affect the chemistry of the tank?

The reason I ask: My tank has a couple of SPS but is mainly LPS and softies. I'm getting the lights to make the tank ready for more SPS but, additionally, my phosphate is too high. I am planning on adding a reactor to reduce the phosphate but I don't want to make two changes at once if the results can not be separated. In other words, if I change two things (lights and reactor) and chemistry goes sideways, I will need to know which of the two changes (or both) caused the problem. If lighting will not significantly change chemistry, then it makes sense to get the reactor setup and going now since chemistry changes will be directly affected by only one thing. If lighting can cause chemistry changes, I don't want to make any other changes before I understand the impact of the lights.

Any assistance appreciated.

Jim

 

[MnFish1]

Yes - it can -- it can increase photosynthesis, coral growth, etc. Thus - parameters can change. I'm not sure that its possible to say 'for sure' what will happen in an individual tank. However, if you're changing your lights slowly over months - IF your parameters change - they should also change 'slowly' - and you should not have an issue.