From the August/September 2008 Issue:

Low-Maintenance Options for Koi Ponds

What is a low-maintenance option when it comes to Koi ponds? — Phil B. in Ewing

Koi ponds have become much simpler to maintain in the past few years, thanks in part to devices called skimmers and external bio filters.

Maintenance used to require placing submergible pumps in the center of koi ponds and rigging them to filtering systems in the bottom. You had to climb into the pond to clean the filters, and the systems were unsightly.

Now, however, skimmers similar to those for swimming pools have been developed for koi ponds. They draw water from the sides of the pond and are cleverly hidden by rocks. Filters are placed outside the pond also and are disguised by plants, rocks, and sculptures, making them easily accessible for cleaning.

It’s important to note these ponds can’t be too deep. Because the pump draws water from the surface, deeper ponds would still get cloudy. In that case, you’ll need a second pump to circulate water from the bottom. Thirty inches deep is your best bet for a koi pond.

You also have to consider the safety of the fish. One misconception is that a deeper pond will protect the fish from predators. That’s not necessarily true because predators tend to wait until the fish surface before attacking. Rocks and caves built in the pond give fish a place to remain safe and also add visual interest.

If you want to forego a pond with koi, try a water feature such as a pond-less waterfall. These can be very dramatic and require little or no maintenance. - DNJ


John D. Butler
president of Arapahoe Landscape
Contractors Inc., Allendale