Pondmaster offers submersible Ultraviolet Clarifiers with the glowing monitor halo ring that immediatly shows it’s working.

1 halo ring
Max flow 600 GPH
9000 hour bulb
18′ power cord
Max pond size 1500 Gallons
6 lbs
3/4″ barbed inlet – outlet
The only ultraviolet light that is submersible, it can also be placed outside the pond. The black color makes it unobtrusive wherever it’s used. Visible during the day and night from any angle, the soft blue halo shows it’s working, but does not detract from the beauty of your pond. These lights offer great value, along with the ease of use unsurpassed by any other Ultraviolet Sterilizer.

Weight3.7 lbs
Dimensions14.75 × 6.75 × 4.5 in