UV treatment before RO

Hello all

I am trying to filter lake water to provide drinking water for my off grid cabin

The lake I am drawing from has tannins in the water. How much does this affect the UV treatment?

I'm trying to prevent bacterial growth on the RO membrane.

Another option that I have access to is a ozone generator with injector left over from a previous owner of my house. I've thought of using that to treat the water before the RO

I'm not really interested in removing the tannins as they are not an issue otherwise

What do you think my best options are?

Thanks