Brenden
Aquarium Advice Addict
Skimmer on or off really does not matter as long as you have circulation. Yes waste makes ammonia but you have no "waste". The skimmer will not work properly for a while until it gets "coated" and slimed up real good so go ahead and run it so when you do add fish everything will be ready. I ran my skimmer on the cycle but ran the waste line back into the sump.