Ozone port cap

[docwells]

I have a BK Mini 160. I lost the ozone port cap. What can I use to replace it? I didn't want to buy something that would not work or be safe for the tank.
Thanks

 

[wvned]

A piece of vinyl hose plugged with a nylon bolt. A solid plastic piece with a hole drilled in it. It depends on what you have to work with.