how many gallons
Well, because of the shape of the pond I really don't know! Is there a easy
way to know?
and what are the dimensions of the pond,
It has a perimeter of 22mt
how deep is the pond
It's 60 cm deep
how old is the pond
It has 5 years
how many fish and how big
There are no more than 40 fish. Most of them have 20 cm
how often do you feed and how much at a time
Once a day, about 50grams of food
how big is the pump and filter
The pump pumps 3000 lt/h
The filter it's a beer size barrel.
It's cleaned once a day by summer, and once each 2 days in winter

Here's your problem. The filter is WAY too small. If you have to clean it
every day to every other day, in my book it is too small by about 30 days
for one part, a year too small for another.

You have two choices to get rid of the green water. Add more plants and
reduce the fish load down until the water finally stays clear, or build/buy
a bigger filter.

I have 5678 liter pond (1500 gallons), an approximately 6 medium size koi
approx. 40-50cm (assuming large is 36 inches/91cm) & 10-12 20cm/6-8inches
koi. My filter is one 208 liter/55 gallon prefilter, and two 208 liter/55
gallon bio-filter. The pump, is turning the pond over once/hour. The
bio-filters are cleaned once/year. The prefilter every 6 to 8 weeks. Now
wouldn't you rather have a maintenance ritual like that? ;-) Not to mention
clear water. ~ jan

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See my ponds and filter design:
www.jjspond.us

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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