Thanks for the reply. It got me thinking, and upon further investigation, I'm not sure those check valves are the real issue (or perhaps they're another issue). They don't seem to leak when held above the water line, which is where they were most likely fastened before the leak degraded the cardboard or whatever they were ziptied to. The zipties are loose and no longer securing the check valves. HOWEVER, It appears that one of the nipples to the waterfall is broke, but not broke off completely, so it's leaking whenever the circulation pump is on. If I slightly pull on the hose going to the nipple, it starts leaking considerably worse. NOW my question is: How do I remove the waterfall and replace it? I can't seem to find any type of nut securing the stems to the shell, but it's quite difficult to see up inside there, even with most of the foam scraped out of the way. Any suggestions?
