Eshopps float valve inlet leaks. What part do I need?

[kinetic]

I just opened a brand new Eshopp's float valve that I bought about 5 years ago.

Looks just like this: https://www.saltwateraquarium.com/rodi-float-valve-kit-eshopps

Anyway, the inlet when attached to my RO/DI is leaking, thus the float valve won't ever work since once that's closed, the inlet is still spouting water.

I've tried their supplied tubing, as well as my own. Even tightening the screw to get it in won't keep it from leaking (in fact doing that just totally stopped the flow somehow).

The inlet is just way too big I think. The tubing just wiggles around and I can easily see how it's not going to hold any pressure.

Any ideas on what I can do? Should I just replace the inlet? What parts can I use to replace it with?

Will this work:
https://www.bulkreefsupply.com/mur-lok-1-4-female-npt-x-1-4-push-connect.html

Or:
https://airwaterice.com/female-adapter.html

Attached to this is a photo of the part, and the area where it's leaking from.

 

[Ty Hamatake]

How far are you inserting the tubing before you tighten the nut? I know a lot of these use a compression fitting or ferrule. Was/is there a small plastic ring for you to insert the tubing into before inserting it into the compression nut?

 

[kinetic]

How far are you inserting the tubing before you tighten the nut? I know a lot of these use a compression fitting or ferrule. Was/is there a small plastic ring for you to insert the tubing into before inserting it into the compression nut?

I inserted it all the way in. I tried part way in too. There's no plastic ring before the compression nut. I could've lost it too.

 

[Ty Hamatake]

Ok, just to make sure we're covering all of our bases. The nut comes off, you insert the tubing through the nut and into the elbow, then tighten the nut? If that's correct then I would suspect it's the missing ferrule that's causing the leak.

I think this will serve your needs, just make sure to match the size of the threads. https://www.bulkreefsupply.com/mur-lok-swivel-elbow-1-4-npt-x-1-4-push-connect.html