Do you have an air ckecker valve for your skimmer??? I am not familiar with Macro skimmer. Sounds like the air injected excessively into your water column. If this skimmer came with the water pump, then you could consider my recommendation below for Andy. If you purchased the pump separately, then you might need a smaller pump.
To Andy:,建議您出水口加些生化棉(或是過濾棉..等),孔隙小一點的,應該就可以解決,目前我就是這樣用
Although I do preach miracle for skimmer. But what you did is actually going to deplete your skimmer efficiency. Do not use 生化棉(或是過濾棉..等 but rather than plastic coil or similar material. like this CPR skimmer:
http://www.reeffanatic.com/cgibin/category.cgicategory=ps_cpr&item=PS_CPRBP2&type=store
Can you see in the water chamber on the left hand side????? It is on the side for the water return. OR if the water return for your skimmer is above water line, you can then use the same material or some bioball placed in the vegetable washing basket and place it below your water return hose, OK?? Just a suggestion if you are using the factory provided pump, OK?? Other wise, check the recommendation on the top regarding pump size.