Nice! I have them in my pond as well, but have no idea what the type is. They are at least 25 years old.
Years ago we “Planted” several water lilies in the pond. One of them originally from a local waterway, has “Escaped” its basket, and its roots have taken over about a third of the pond. In the last week, as usual for this time of the year; it is pushing up purple flowers, two and three at a time. It has green lily pads. The other is an exotic of some sort, that remains rather modest. It has reddish green pads, and white flowers. Its pads are rather small, and never seems to expand at all; only flowering once or twice, every second year.
We do not filter the wated, allowing it to remain natural, just as the local rivers look. The lilies do a grand job of keeping the water healthy, and the gold fish keep breeding like mad.
I’m going to add several Koi to the group in the next week or two. A friend breeds them in his pond. I’ve had them in the past, but keep giving them away to friends. They do tend to be a bit more aggressive than the plain old Goldfish.
The pond is 12’ x 6’, and 4 feet deep…over 20 years old…