that can be from a leaf to a racoon's little paw reaching out to ur koi when ur out partying hard
but they do sell (koitoys
) out there and there is alot of diferent kinds but the coolest one ive seen and had before my killerkoi became one large order of sashimi
was called a tug-a-bell it was a small fishing float and one side on the top had a small bell and the bottum was a thick 15''long fishing line with a lite led wieght colored bright oranges and when they past by it the koi would grap the wieght and the bell would ring so even if u near the pond u would hear the bell a think FISH ON!!!!!!
OH BTW that is ironic 