Skimmer and ats

[ethom0816]

I'm running both right now do you think I need both it's a pain in the butt getting to the skimmer cup to clean it

 

[lavoisier]

Again, that will depend on what you want to keep, which will determine what parameters you want for nitrates, po4, orp, and dissolved oxygen. You can certainly run a skimmerless system but it may limit your choice of corals.