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Plants
and Fish
For a garden pond to be successful, it must contain both plants and fish.
Not only is this an optimum esthetic condition; but a balanced biotope
with interactions between plants and fish will ensure proper water conditions,
reduce insects, especially mosquitos, since the fish consume their larva,
and plants will greatly reduce the development of algae.
Plants and fish benefit each other in two ways. First, fish and plants
contribute to the successful functioning of the nitrogen cycle. As the
waste products excreted by fish are released into the water, they are
converted to ammonia and then to nitrites and nitrates by nitrifying bacteria.
Nitrates are a food or fertilizer for plants and algae. As they are absorbed,
plants and algae become a valuable food resource for fish, thus completing
the nitrogen cycle.
This ongoing biological cycle ensures healthy pond life. It is important
to realize that if plants are not thriving, algae will take over and the
water will become murky.
A second important way fish and plants complement one other is through
the process of photosynthesis. Fish require oxygen for their existence
and they release carbon dioxide. Plants in turn require carbon dioxide
for their successful existence and emit oxygen. During sunlight, plants
will consume the carbon dioxide released by fish and in turn emit oxygen
required by fish.
A constantly functioning nitrogen cycle and photosynthesis are the key
components to a successful and beautiful garden pond. The most beautiful
type of pond plants are lilies. Water lettuce and water hyacinths are
also excellent additions to the pond and submerged plants such as Hornwort,
Vallisneria, Sagitarria, Cabomba and Anacharis are also excellent. The
ideal pond fish are common or hardy goldfish.
Weekly Tasks
• Check the water level--if it has dropped due to evaporation, top
it off. Add a dechlorinator if you add more than 10% of the total volume
of water. If it has not dropped, pump about 5% of the water into the surrounding
garden and top off the pond. The water is great fertilizer and the water
changing deters chemical buildup that can corrode the pump.
• Check the bottom of the pond for decaying vegetation
and remove dead plants, leaves or other vegetation. Dead and decaying
plant material can foul the water and kill the fish.
Monthly
Tasks
• Fertilize your water lilies with a product made for aquatic plants.
Follow the manufacturer's directions for application. Fertilize the lilies
from the time the leaves reach the surface in the spring until the lilies
go dormant --usually about the first of November.
•
If you have a filter with your pump, clean it every month. During the
hot part of the summer and if your pond is in full sun, clean it more
often. If the filter has a foam rubber component, run water through
it until the water runs clear. Do not squeeze or wring it out.
Yearly
Tasks
• Remove all of the fish, plants and pump out the water. Lightly
scrub the bottom and sides of the pond with a brush--do not use chemicals
or soap. Add new water, dechlorinate, replace fish, divide plants, repot
and replace. Save some of the old water to store the fish in while the
pond is being cleaned. Put the fish in plastic bags in the old water.
Float the fish on top of the newly cleaned pond until the water in the
bag and the water in the pond are the same temperature. Late February
is a great time to do the yearly cleaning. Make sure the temperature
of the water is above 55 degrees.
Pond
Care Tips
When your pond is new put a dechlorinator in the water. Both chlorine
and chloramine have been added to the water and our fish and plants
cannot live without adding dechlor. Add the dechlor according the directions
on the bottle. If you make a mistake, put in too much rather than too
little. Too much cannot hurt the fish.
What About pH?
pH is an indicator of the acidity or alkalinity of water. Water below
a pH of 7 is acid and above 7 is alkaline. Ponds that are near 7 are
usually clear. As the water gets green, the pH rises because the fertilizer
from the plants or fish releases ammonia and feeds the algae. If you
have enough submerged plants, they will absorb the ammonia and you will
not have green water or an unbalanced pond.
What About Koi?
A Koi is a scavenger fish that will eat anything--water lilies, hyacinths,
submerged plants and will jump up to nibble on plants growing around
the perimeter of your pond. If you want Koi, you cannot have submerged
or floating vegetation.
Liners
The most important part of your pond is the thing that holds the water
in--the liner. The sun is its worst enemy. It will destroy a liner faster
than any other natural enemy. Cover every piece of your liner with finishing
material, whether it is rocks, bricks or other material. While I am
on the subject, use liners made for pond use. Buy your liner from a
store specializing in Aquatic Garden supplies.
Finding a leak
Chances are your liner is not leaking at all if you are losing water.
Evaporation is usually the cause of slowly lowering water levels. If
the water level falls significantly overnight, you are most probably
losing it by water falling off the back of a waterfall or if you have
a fountain, the wind has blown the water out of the pond. Or if the
water is falling from too far up, it is splashing out. Check all of
these things before you suspect a leak in your flexible liner. If you
have finally determined that your liner is leaking, your biggest problem
is finding the leak. Most liners have some sort of patching material,
much like cold patching a tire, but until you find the leak, you cannot
patch it. I have found that pumping the water out of the pond and then
running water under the liner is the best way to find that undetectable
leak. Here in New Orleans, the water will come up through the hole when
I get water under the liner. I know it is a pain in the neck, but I
have yet to find a better way.
Catching fish
Getting fish out of the water when it is cold outside: Why on earth
would we need to know that? Sometimes fish have some sort of disease
and treating the entire pond is almost impossible, but treating a few
sick fish is economically feasible. Pour warm water into one end of
the pond. The fish will come toward the warm water and right into the
net you have conveniently placed there.
Recycling
When you change some of the water in your pond, use that water for the
rest of your garden. You can't find a richer source of organic nutrition.
You can recycle up to 5% of your water weekly if you like, thereby helping
the planet and saving on your water bill.
How much does it cost to run a submersible pump?
Electric costs are easy to compute. I am often asked how much it costs
to run a submersible pump and if there is a difference between brands.
I will use the example of a 100 watt light bulb and a utility cost of
$0.08 per KWH. A KWH is a kilowatt-hour or, 1,000 watts used for 1 hour.
A 100 watt light - .1 kilowatt or .1 KWH = less that 1 cent per hour.
•
Find the actual wattage used by the motor. (If the actual amp draw is
not available, estimate by using the full load amps plate.)
•
Watts = volts x amps for single phase motors. The light bulb has an
amp draw of 8.7 x 115 volts = 100 watts.
•
Compute your cost per month by multiplying the KWH x 24 (hours used
per day) x 30 (days used per month) x cost in KWH (to find the actual
cost look at your last power bill and divide the total power charges
byt KWH used).
How Much Water do I Have?
This is the formula for calculating the number of gallons of water in
your pond. Because most ponds are irregular, the capacity will be =
or - based on various contours within a rectangle or square (in gallons)
