LF UV filter to buy or borrow in YYC

[Scott7]

I want to give a UV filter a shot for a month or so against Dino’s.
It’s only a 20g tank so don’t need anything big.
I do t want to spend much as it will hopefully not be permanently in use, and I dont even know if it will work.
If you have one laying around I’d be happy to buy, or borrow.
Thanks!