Plant Doctor Archive

Water Gardens — UV clarifier

SHOULD I switch off my UV clarifier during winter, as recommended by the manufacturer, and bring it inside?

IT depends entirely on where you live in New Zealand. The reason that pond equipment manufacturers advise that the units be brought inside is that severely cold weather (we're talking about freezing temperatures, with ice and snow) can cause the quartz glass sleeve to split and they are expensive to replace.

Also, ponds are unlikely to go green in winter and turning them off will extend the bulb life.

In Auckland it is unlikely to get cold enough to warrant this procedure (I hope not anyway!) and many modern UV filters have a Teflon sleeve, so I leave it to you to make your own decision.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.