Has the pond been cleaned?
Did the previous owners tell you any history of its maintenance?

I think I'd clean out the pond. Pump out the pond's water.
Should take a couple hours - I have a 3,000 gallon pond. After you've got
almost all the water out, remove fish via net to a netted kiddy pool ( in
dappled shade if you have it, not full sun) filled with the pond's water. If
fish gasp at the suface add a bubbler to get more oxygen in the water.
Then scoop all the glop out that is on the bottom of the pond.
Makes good fertilizer. Do not scrub the sides. Refill, add dechlor or
dechloramine depending on your water supply (call your city and find out if
there is ammonia in your water), let the temperature get pretty close to the
water in the kiddy pool, put fish back in.
This is usually an all day affair. Order pizza, have beer and/or soda on hand.
It helps if you have a couple teenagers at home.

I'll post the green water hints below for you as far as future maintenance -


Algae fighting tips
~ Nutrients for all forms of algae are sun, new water, fish waste, fertilized
run off, rotting plants, blown in dirt.
~ New ponds and spring ponds need time for plants to get established, algae is
quicker at getting going.
~ add plants, of any kind, in the pond. Especially underwater plants.
~ Shade is good - provided by lily pads, floating plants or artificial shade
for part of the day.
~ LOW fish stocking (20 gallons per goldfish, 100 per koi after starting with
1,000 gallons) and *not* overfeeding the fish. Too many fish and too much
feeding is probably responsible for most pea soup water, followed closely by
too much decaying plant matter, sludge and overall gunk in the water
~ adding a combination mechanical and biological filter to screen gunk and
convert fishy ammonia waste for fish health.
~ do not use algaecides, they only make lots of suddenly dead algae
and that will feed the next algae bloom.
~ do not worry about algae that grows on things (substrate algae) this is good
for a pond
~ gently remove string algae
~ build a veggie filter, to run water through plants
- as easy as floating water hyacinth in your filter or
Ingrid's post on plant filters:
The essence of a plant filter is a water proof container with the water from
the pond
being pumped in one end flowing thru the roots of various plants and flowing
back
into the pond at the other end.
It needs to be long enough that solids settle to the bottom OR have filter
material
that will slow or hold the solids (and get rinsed out periodically).
It needs plants of different kinds to maximize removal of all wastes.
it needs sufficient amount of plants to remove in one day all the wastes
produced by
the fish load in one day. It needs plants with extensive roots and/or plants
that get big so they used up more
nutrients. It needs to be only 8-12" deep so it doesnt go anaerobic.
~ clean up dead plant matter and screen for falling leaves
in the fall. Clean out pond once a year.
~ water movement, occasional water changes of 10%
~ add a sludge consumer, concentrated bacteria.
many rec.ponders use http://www.united-tech.com/m-aq4u-toc.html
~ Check your pH, too high, over 8.8, or too low, under 6.4, and most higher
plant forms can't take up the nutrients.
~ building ponds with bottom drains and skimmers.
~ UV lights work on suspended algae (green water) - does cost some $$.
~ patience and time ;-)



kathy :-)
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