You don't need a large elaborate fish pond. This simple one is perfect to manage and enjoy your koi!
wooden raised pond - Google Search
Railway sleeper pond, pergola and raised beds
raised railway sleeper pond
How To Build Your Own Pergola More
above ground turtle ponds for backyards - Bing Images
Looks very similar to the moray eel my brother-in-law caught while fishing off the pier in Bodrum. Not quite what he was expecting to catch. Putting it back in the water was as frightening as its teeth.