The most noteworthy quality of this kind of pool is its versatility, for an ornamental pool can be set up to accommodate not only stocked fish but wild visitors as well, creatures like frogs, dragonflies, and water striders. And there is not just one kind of fish that is appropriate. Pumpkin seed sunfish, chub, black bullheads, or bitterlings live in a well-tended ornamental pool just as happily as goldfish, golden orfes, and kois. Such a pool is also a wonderful place for the many beautiful cultivated varieties of water lilies.
What You Should Know: If the pool community of fish, plants, and visiting creatures is to thrive, some care has to be taken in setting up and maintaining the pool.
– The pool should have a minimum size of 65 square feet (6 m2), and there should be a deep-water zone of about 10 square feet that is at least 32 inches (80 cm) deep so that the fish can overwinter in the pool.
– Fish as well as wild visitors will thrive only if you proceed according to the motto: to each his rightful place. While the areas of open water will naturally be claimed by the fish, amphibians and other pool visitors need a different kind of environment. For them you have to create a fairly large marsh area that is fed water from the pool but is separated from it by a stone wall. Many amphibians (like newts) prefer not to have fish close by and therefore need their own terrain, namely a shallow marshy strip next to the pool. This marshy part should be densely covered with vegetation and may dry up almost completely during the summer. Having this shallow zone also keeps goldfish from eating up all the eggs of amphibians.
– A pool profile resembling that of a soup bowl with a flat rim is ideal but hard to realize in a very small pool. In order to end up with a shallow-water zone and an extended marshy area, at least part of the pool’s bank has to be built somewhat steeper.
– Neither fish nor water lilies like to have water pouring down on them. It is therefore better to do without fountains that send jets of water high up into the air. However, something more modest, like a bubbler stone, a small fountain with a gentle splash, a spill pipe, or a tiny waterfall can be harmoniously incorporated into the overall design of an ornamental pool.
Location: Choose a spot where you spend most of your time and where the pool forms part of your view. The pool can be very close to your house, directly adjacent to a patio or terrace, for instance. Of course, any other spot in the garden is fine too, as long as it receives five to six hours of sunshine.
Materials to Seal the Bottom: Use either a pool liner or a preformed fiberglass shell.
Plants: Choose anything¡ªfrom Nymphaea water lilies, floating hearts, water soldiers, and the yellow water lilies (Nuphar lutea) for the deeper area to the numerous marsh plants, like irises, lobelias, water plantain, purple loosestrife, and marsh marigolds, to name a few. There is much to pick from when you plant an ornamental pool with a shallow-water zone and a marshy zone.
Please keep in mind, though, that restraint is the mark of a master. Fish do not thrive in water that is shaded too much by water lilies, and many marsh plants are so prolific that they crowd each other out.
Animals: Since fish multiply in a pool that is well kept, restraint is called for here too. Also keep in mind the natural behavior of different kinds of fishes. Bitterlings, for instance, rely on mussels for “nurseries,” and mussels need a sandy bottom. Sticklebacks are fierce predators that eat anything that moves¡ªdon’t get more than two pairs. Goldfish come in many varieties, but not all of them are suitable for an ornamental pool (see the next section, A Goldfish Pool); the decorative veiltails, for instance, tend to present problems. Blunt-nosed minnows do well only in groups of at least five to nine fish.
Upkeep: Good filtration of the pool water is essential because uneaten food and the excreta of fish can quickly foul the water. You can filter the water with a special pool filter or, ideally, by circulating it through a stream which¡ªif properly built¡ªwill act as a biological filter. You also have to make sure there is enough oxygen in the water. For this you need an air pump.
Fall is the time for a thorough cleaning of the pool and for plant care in preparation for winter. In areas where temperatures may remain below freezing, small pools should have a deicer or be covered.