This is a question that everyone asks when they are thinking of creating a koi pond or adding fish to an existing pond.
The answer is that it’s just like buying a car. There are expensive ones and there are cheap ones. Sometimes you can over pay. Sometimes you get a bargain.
The first thing to do is to narrow down your choice by what sort of pond you have or are going to create.
Firstly, what size pond is it? Will it be in the right situation for fish?