Yup, quite a few lakes are lost to the native Nuphars, they do trot off into deeper water quite rapid, in numbers. there are small forms that you might consider, possibly, the Cape Fear Spatterdock and a miniature form which don't like deep water, though those are hardly available commercially
Any of the medium to large hardy waterlilies will create quite well behaved groups of shading plants, you might add Water Fringe, aquatic Iris, Pickerel and Arrow Arum as well, in up to one foot depth of water. When they mass up they won't cope with water any deeper.
Plants like those will increase the range of habitat to encourage fish fry in areas sheltered from larger predators
Regards, andy
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