Hi all, We have a Paramount MDX R3 bottom drain and an SDX sidewall safety drain which are plumbed together and feed into the Paramount leaf catcher deck canister. We have removed the SDX cover (via the 3 security screws) and are attempting to blow the line out and cap, however, we can't figure out the correct cap/fitting. We have had multiple calls with the regional Paramount rep today (who has been very helpful), but he does not know the cap size. The black plate of the SDX which is attached to the side wall of the pool has a threaded end (similar to a normal plumbing return), however, no one knows what size threaded cap (with rubber O ring) to use to close this off. We have tried rubber compression fittings, and while a #11 appeared to fit, it then popped out. Please help! Thanks!