I'm putting together a fountain feature in my yard and I'm using vinyl tubing from the pump to the bottom of the feature (which has a copper tube inside). I've got a compression union to connect the two, and I'm pretty sure it'll work fine on the copper side. But on the vinyl side everything I see indicates that I should use a plastic sleeve on the outside of the tube inside the compression nut.
In this case, however, the fitting that I picked up has captured brass sleeves (by which I mean that they're attached to the nut, not a separate piece).
Is this likely to damage my tubing? Should I pick up a different fitting or can I just be extra careful about over tightening?