Assess Pond Obstacles

This is a pond I built early on. Rocks to cut the Koi's faces, see?

Don't forget this step, because MANY ponds contain engineered obstacles, whether intentional or not. Rocks perched on the ponds' edge can cut the faces of Koi which surface to eat near the pond's side. Some ponds are engineered to have rocks on their ledges, and when the Koi access these ledges for foodstuffs or simply by way of exploration, damage can be done to their bellies or other exposed skin of the face or gill-cover. Substantial sharp-edged boulders in the pond can also lacerate a koi that swims into the rock when dashing from a fright, or at night while sleeping. Certain skimmer parts and filtration accoutrements in the pond bottom also cut any fish which swims into them. If fish are sick or showing up with sores or wounds, assess the pond for injurious obstacles into which they may be swimming. A skilled pond installer can install rocks, boulders, and other decorative and natural looking objects into a pond design with sensitivity to where the fish will be fed, and how they will safely move about these objects. Some sharp, already-deployed obstacles can be wrapped in liner underwater to make them harmless to the fish.

Go To Step Thirteen

Supplemental Reading

Rocks in the Pond: Gravel Bottom Ponds - Noxious Gases or Infallible Low Maintenence Koi Pond and Water Garden Filtration? - Article by Dr Erik Johnson