Brown Water in Pond - Well Brewed Tea
Doug says
Brown water like this usually means one of two things.
The first is organic matter in the pond and this could be as simple as that "nice log" you just put into it for the frogs to sit on.
The second common cause is using peat moss or artificial soil in the lily soil. This will turn water browner (and is a very common cause) faster than anything I've ever seen.
The solution
The solution to both of these problems is to remove the log and repot the lily into a heavy clay natural soil containing no peat moss. (Almost all soils you purchase in bags contain some amount of peat)
In General
In general, brown water indicates a high level of organic matter in the water. Sometimes it is rotting leaves or other substance but the deal is the same; you must get rid of the cause. Generally, cleaning the filter is step one (after removing logs/peat-soils).
There are compounds available in pond shops that act to "bind" the small dirt particles and drop them to the pond bottom where they can be cleaned out. Vacuum the pond bottom to remove them or get them in the normal fall cleaning.
Clean Your Pond
If you haven't cleaned the pond in a few years, here's a clue that something is wrong and need doing. Your natural pond bacteria sources (gravel or rocks in the pond bottom) are plugged up and can't do their job.
pH Problem
You might have a pH problem in your pond as well. High levels of organic matter can't be dissolved or attacked by pond bacteria if the pH of the water is over 8.0 or under 6.8. Do a water test.
There are compounds available that will adjust pond water.
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