UVS system for 500l tank

[Discus Dan]

Can anyone suggest the most cost effective UVS system, that is still effective? I have a 500l aquarium and have been playing with the idea of an ozone generator, until someone suggested a UVS. Preferably one that is part a filter.

Thanks.

[FishLover]

36w Jebo

[Davo]

De Bary are a quality brand. The 15 watt or 25 watt would do it. I would get a stand alone UVS as they are apparently more efficient.