Koi and plants do fine if there are enough plants and enough decor to keep the fish occupied. Yes, Koi get bored.
Koi and plants do fine if the plants are abundant enough. If you "try" one or two plants to see how it goes the group of Koi will consider them quite the novelty and will probably allocate a lot of time to checking them out. Not having thumbs, they experience their world with their mouths.
If there's ANY gravel in the pond, they will spend time sifting that, and rolling the rocks around, and playing with the plants, and then the plants aren't the sole entertainment.
HELP! Sick Fish! Twenty Steps to fish health. You LITERALLY can solve almost any Koi or Pond health outbreak with these twenty diagnostic steps and nothing's hard. But it's not "here's your pill" either. Downloads are available.
DrJohnson.net More than koi health, this site spans all things animal, by a real veterinarian who shoots you straight.
Fishdoc.co.uk By Frank Prince-Iles. A UK authority who put this site together some time ago and which is still relied upon as a major source of good Koi and pond fish information
If you need pet information AND Koi pondfish and pond information you might like DrJohnson.com which has everything from pet info, to vet info, to koi and pond fish. It has it ALL! Pet Information.
If you need pet information AND Koi pondfish and pond information you might like