With a nitrite level of 5, your filter has not completely cycled. That high
a nitrite level is dangerous to the fish, without salt in the pond. Add
about 1 pound per hundred gallons to get a salt level that will protect the
fish. Once the nitrite levels come down to 0, then remove the salt through
water changes. Plants, and particularly algae, like their nitrogen first
from ammonia, then nitrites, and then nitrates. With an uncycled filter,
you have some minimal ammonia left, and high nitrites, so the algae is
thriving.

Filters are marketed with a pond size in gallons, liters, etc. This is very
poor, since the size of a filter should be based on the amount of waste,
which is associated with number of fish, turtles, frogs, etc., size of each,
number of feedings, water temperature, etc. Most filters are over rated by
a factor of at least 2. I run filters that will supposedly handle about 4
times the volume of my ponds.

I am assuming, by your pH, that the hardness value you stated, is the GH
hardness, not the KH carbonate hardness. KH helps to stabilize the pH and
helps the filter bacteria, which consume a certain amount of it. If you
have not checked it, then please do. The level should be a minimum of 100,
and can be as high as 300 without harm. To raise the KH, use regular old
baking soda.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html

"KerplunKuK" wrote in message
...
George scribbled :
Perhaps if the person posting his question could post his water parameters
(pH, ammmonia, nitrites, nitrates, general hardness), we could give him
more
specific information.

The results from the testing are as follows;
pH= 7.6
Ammonia= 0 - 0.125ppm
Nitrite= 5ppm
Nitrate= 0ppm
Hardness= 201-300 mg/l

Anything else needed? My next step is to introduce many more plants. Are
there any that are especially good, or is any plant good?
--
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