Just use a different pump?? WOW, i can't believe i read this. Below I give you a few explaination why you're totally wrong. #1, FYI, the size of the neck of the skimmer depend on the pump. too big will not be strong enough, too small will cause the bubbles to raise to the top. #2, Also, the impeller play a big part in it as well of the venturi as this almost need to work together to creat fine bubbles. That's why you see some skimmer out in the market doesn't work because they use the wrong pump and their impeller and veturi doesn't work together. #3, you can't just use any pump because all the pumps PVC fittings are all different. Not just that, the size as well. So is almost near impossible to find one pump fitting to fit another. So NO is not possible just to use any pump with any skimmers.