I need to remove the sand and check the laterals because we're getting substantial sand in the return lines. So of course, the water won't clear and I'm worried that the sand coming through is damaging the rest of the system. So I replaced my shop vac, got all my tools, including the wrench that came with the filter, sent the kids out so I could concentrate and get the job done and I can't get to the sand, much less the laterals because the collar is stuck. Honestly, I don't know what else can go wrong this year. *sigh* I removed the nut and bolt that secures the collar, but that collar just WILL NOT MOVE. I put some silicone spray on it (heaven help me if *that* isn't good) but I don't know what else to do here. Am just about in tears, I'm so frustrated. It is a 19 inch waterways millenium series filter. Please, if you have *any* ideas, let me know. Thanks.