These mini filter is good product. I use it with my 18 L tank as second filter with Jebo 502.
Both of them keep my tank crystal clear.
Jebo 502 is easy maintenance, while Resun CY 20 is a good canister filter, small and reliable.

Very good filtering!

I use for my 112L marine tank, great filtering, almost no redslime after 7 days use! great for lps and sps to keep nitrate down.

Fine product.
I had to use silicone on the tubes because there was dripping. Besides that its a very good product.
I use it in my shrimp aquarium. 17 liters.

I juse it in my refugium as a hang on particel filter and i altso gone use it in my quarantine tank.
Easy to clean,small and no noice .