Any chance of you going deeper than 3ft, I'd try for an extra foot at least, most koi keeper go between 5/6ft when building a koi pond. As your building a ledge, this will make it easier for a predator (Heron) to wade in and snap-up your fish, 4ft would give them a bit more security and growing room in the pond.
Shazz
Posted on Aug 19, 2005, 12:40 PM from IP address 80.176.91.232