We bought a house with an above ground pool last year. Vinyl Lined, fiberglass exterior (I believe). Sand filter. Circulation has been an issue, so we looked at the return and there isn’t a jet. We bought one. It wouldn’t screw into the fitting. Then I noticed after looking at so many parts and possible reasons why, that there is maybe
a lock nut on the inside of the pool over a flange (terminology is possibly incorrect… sorry), where I’ve only seen that the lock nut should be on the exterior of the pool. That explains why the jet fitting won’t fit. Can I just take the lock nut off without having any damage to the pool wall or construction of the plumbing to the return?? Or do we have to replace the whole setup? I’ll have to take a look once the current deluge of rain is done and see if there is also a lock nut on the exterior of the pool where the return hosing is connected from the filter. Any help is appreciated.