Can a UV Sterilizer be to big?

[Millz034]

I am looking into getting a UV for my 25 gallon Cube with a 10 gallon sump.
I am currently fighting dinos and want to help the process with a UV. I was looking at the Aqua UV 15w Advantage 2000+ hang on but the 8 watt version is a little cheaper. I am wondering if the 15 watt will be to big and just go with the 8 watt.
Or is there such thing as to big of a UV.

 

[PeterC99]

I’ve always been told to oversize the UV light. Have a 57 Watt on my 90 gallon. My Water is crystal clear and no problems with dinos or cyano.

 

[JayA]

I have a 5 watt in a 20 gallon tank. Does the trick when I use it for dinos.

 

[|Tom the Bomb|]

You could potentially oversterilize your water but thats more like 100W on a 20 gal I think the 15W would be a perfect size (35 gal)