Runners are great ducks, come in many colors, most hatcheries and local feed stores carry them, and lay big nice eggs regularly.
All ducks love swimming though........ my runners isn't a big fan of swimming and doesn't do it very often(once a day maybe)
How deep would your pool be? It needs to be deep enough so they can splash themselves all over and can dip their whole head in.
Here is some duck basics:
Feeding: You can feed them UNmedicated flock raiser or game bird raiser. At night they do not need have to have food and water (if it's really hot out then give them water)
Make sure they always have food and water together, never just give them food.
night time: keep them locked up at night in a safe hut/coop that is predator safe.
Bedding: straw, shavings, or animal pellets.
Predators: Birds of prey(Eagles, hawks, etc.... Big birds) Coyotes, skunks, opossum, RACCOON!, dogs, Big cats, Etc.........
Ask as many questions as you like!