Pond UV different than a Reef UV?

[PFoster]

The rating is very very different.

For QT sterilization you want 90,000 µw/cm2.
You need to match the light output and the flow rate to get this.

For example, our UV sterilizer:
30,000 µw/cm2 (EOL) 35,000 gph
45,000 µw/cm2 (EOL) 23,333 gph
60,000 µw/cm2 (EOL) 17,500 gph
75,000 µw/cm2 (EOL) 14,000 gph
90,000 µw/cm2 (EOL) 11,667 gph

This same UV sterilizer will clarify a 100,000g pond

When a UV sterilizer is rated for pond they give you the pond volume that it will clarify.
Call the manufacturer and ask what flow rate you need to pass through it to give you 90,000 µw/cm2 and this will kill everything down to the protozoa level and stop disease in your qt system.