About a month ago I had Checker replace the sand in my sand filter. Immediately when he turned on the pump there were bubbles coming out of the return. I said "why are there bubbles coming out of the return. I've never had bubbles coming out of the return?" Mike just basically blew me off. Bled it to get the air out and still have bubbles. Had their tech guy out and he was just plain rude. I told him to humor me and check the O ring on the filter lid because I never had bubbles coming of the return and the only thing that has changed is they changed the sand. The guy didn't want to do it and didn't do it and preceded to tell me how he gets paid. Bottom line, he just wouldn't get paid enough to check the O ring and heaven forbid he had to replace it. I've never dealt with a company that won't do something you have asked.