For the screw fitting, if you use a sealant ensure that it is made for plastic and that you do not overtighten. Other option is to ditch the screw fittings and use slip fittings with glue. I don't like messing with the screw fittings because they can be finnicky.
For the barbs, if it leaks the tubing is to large. The tubing should be hard to push on (if you struggle pushing it on, just hold it under some hot tap water). Then use a proper clamp. Zip ties tend to apply inconsistent pressure. Do not use metal clamps. This is what you should use (you can find them on amazon too)
Ratchet clamps are perfect to secure Braided Vinyl tubing to barbed fittings. If you are using silicone or traditional thin wall tubing we highly suggest measuring the outside diameter of the tubing you will be working with to select the correct ratchet clamp. Choose from ratchet clamps for the...
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