Water Gardening
One of our favorite past times is
enjoying our water garden. The water fall provides soothing
noise and tranquility. We enjoy feeding and watching our
fish. Last summer we had 5 resident frogs
that just showed up to add more interest. We also had a
constant colony of Monarch
butterflies
visiting our plants to add even more interest. Our
water garden was one of our best investments.
Maintenance
Water gardens require only minimal maintenance if set up properly.
I spend perhaps a 1/2 hour a week in total maintenance. 
Ask 10 experts or read 10 articles on filtering and cleaning
and you will get 10 different opinions on filtration and cleaning.
Filtration
Most experts recommend a filter system unless there are no fish.
A few admit a filter is optional if only a few fish are kept.
Since filters also require maintenance not having one saves time.
I only keep 8-10 small gold fish and a lot of plants. Just
about everyone agrees that you can not have too many plants but
can easily have too many fish. I have no filter and my water
is as clear as those who have them.
Cleaning
This is another area of much disagreement. Some experts
insist the pond should be drained and cleaned every Spring.
That way the water temperature from the tap is approximately
the same as the old pond water and is easier on the fish. Others
say it should be done in the Fall since the fish are distressed
from over wintering and Spring cleaning will cause more shock.
Some say both the walls and bottom should be scrubbed while others
say only the bottom should be cleaned since the algae growth
on the sides is beneficial to the pond in maintaining proper
chemical balance and provides food for the fish. Other
experts recommend the pond should
only
be cleaned every 3 years or so or when the bottom muck is about
3/4 of an inch thick. Still others maintain a pond should
never be cleaned since it could take up to 3 months to get the
pond in balance again. They recommend just scooping out
the muck with a net from time to time.
This is what I do. My pond is two level with a water fall. I drain the top each Fall for winterization. I have found that the pump seems to pull up the sediment from the lower portion and deposit it in the upper part. Therefore all I have to do is sweep up the upper part before starting up the pump in Spring. I just purchased a vacuum that attaches to a hose to sweep up any sediment and gravel in the lower half. It works fairly well but adds water in the process so the pond level has to down before you start.
Plants
I like the look of a full grown lush pond. I have many
plants. You need a combination of floaters, marginals,
and submerged. I also have one water lily. Between the 
lily and the floaters about 75% of the surface
is covered. This is the recommended percentage to provide
shade for the fish and cut down on algae. Having a couple of
floating water hyacinths which multiply prolifically will prevent
most algae. They use up the nutrients algae need to survive and
block sunlight. In fact water hyacinths multiply so quickly
that it is illegal for them to be sold in 12 warm weather states
lest they find there way into streams and lakes. String
or filament algae is another matter. I just scoop it out
with a small plastic leaf rake about once a week. You can
add barley straw if you wish. As it decomposes it adds
a chemical to the water that prevents this type of algae from
sprouting. It won't kill algae already growing though. It is
available at Bordines and by mail order.
Some people however ,especially those with koi, prefer a sparsely planted pond to better see the fish. In this case a filtering system is more likely needed.
I fertilize the plants with special tablets once a month in cooler weather and twice a month during July and August. Plants multiply prolifically and need to be divided each Spring. The floaters and submerged plants will not winter and should be treated as annuals. They are very inexpensive anyway.
The other plants unless they are tropical will winter nicely if placed in the deepest part of the pond for the winter. Tropicals can be stored in the basement over the Winter or discarded and treated as annuals.
Fish
I recommend cheep goldfish. Goldfish will only grow to
size of the pond. They also secrete a hormone into the
water that when it reaches a certain level stops their growth
and they also stop reproducing. Koi on the other hand keep
on growing and reproducing and can outgrow a small pond.
I also have a problem with hawks attacking
the fish until the plants take over and offer protection.
Last year I lost 4-5 fish. It is better to replace a $0.25
fish than one costing many dollars. I feed them once a
day when I am home. When on vacation they take care of
themselves. Some people with a well balanced pond never
feed theirs. Anyway you stop feeding them when the water
temperature drops below 50 degrees. Feeding them after
that will kill them since the fish can not properly digest the
food at low temperatures and will die of food poisoning. When adding
water the clorine must be removed. You can add declorinator or as a
trick I read about, if only topping off for evaporatoion, spray the pond
with a garden hose. The clorine will evaporate in the fine spray
before hitting the pond. I have been doing this for a year now and
the fish are fine.
Wintering
I remove the pump and store it in a bucket of water so the seals
don't dry out. The hardy plants are stored at the bottom
of the pond. The floaters and submersibles
are removed. It is important to keep the pond leaf free.
Rotting leaves in the water will deplete the oxygen supply over
the winter and kill the fish. A net will solve most of
the problem in the Fall. I then place a floating heater
that keeps a small hole in the ice for gases to escape and oxygen
to enter.
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