skimmate with no biolad

[toytech]

So recently ive set up a 120 gal with a 30 gal sump and its the first time ive got to fire up my SC 150 skimmer I bought new 3 years ago . The tank was set up with around 75-80 lbs of rock I cleaned , bleached , and dried from my old tank and around 15 lbs of live rock and has been running for over a month now . Ive gone though a cycle and now its the usual algae on and offs and is just ticking away with no fish and only a few hermits and the whole time the skimmer has been pulling thick skimmate . I clean the cup every three days , inch and a half of dark , stinky skimmate, and there is a quarter inch of buildup in the neck .I cleaned it yesterday and today there was an inch of quite dark skimmate and a lot of buildup again. I figured it would have slowed down by now but dosent seem to be , is this normal ? seems a little excessive to me.