When should I start skimming?

Well I don't have a sump to use it in wish I did though. Not that much bubbles after the unit has been broken in. Theres a mod that you can do to get rid of the box. Trying to set that up now.

As for skimming. I came home tonight got some gunk in my cup, just a small amount though. Guess it's working but slowly due to no bioload. I think I'm just gonna keep it going for a few days per week. Heard you shouldn't run it all the time. Is this true? My clown like hiding out around the box. Seems like he like the water bubbles dripping from over the side.

 

My internal airline skimmer as been running now solid for around 4/6 weeks tank is 8 weeks old, it takes out some right crap and smells like sewage too, but all seems fine so far, i have no sump or refugium, just external cannister not even done a water change yet or cleaned the filters, nothing, all water parameters are great , nitrates 10-ppm, go for it...