I have that skimmer and to be honest.... IT SUCKS!!!!!!!!!!
REPLY ABOUT IN AND OUT ARE CORRECT.
THE PROBLEMS I HAVE INCLUDE:
1. VENTURI AIR INTAKE CONTINUES TO GET CLOGGED AND REQUIRES CONTINUOS "UNCLOGGING"
2. THE SKIMMER WILL EITHER OVER SKIM (I.E. TO MUCH BUBBLES/FOAM), OR NOT ENOUGH
I HOPE YOU HAVE BETTER LUCK THEN ME!!!!!!!!!!!!!