Thanks Meyer. I'd be happy with 18 inches of visibility but mine is about 2" and it became that way 1-2 years before any fish were introduced. That's why I think something else can be done to help the clarity. After doing some research I have decided mine is now only planktonic. There are NO visible particles in the water. They must be microscopic. There is also NO sediment in the sample either. I have a large fountain for aeration.. Thanks for steering me away from a bog filter. I feed them a small amount once a day. All is eaten within 5 minutes. If the water temp is under 50 I give them nothing. How will I know if they ever need to be fed again?
Is this a surface intake fountain or does it draw from the bottom of the pond. The pond water needs to circulate. This can be accomplished by a pump or a bottom draw fountain or a diffuser. Of the three, the diffuser is the best because the air bubbles lift the water imparting a rotating water current from top to bottom to top again. This greatly improves the Oxygen levels of the pond and circulates this Oxygen to all parts of the pond.
Quit feeding the fish. You will know if they require supplemental feeding when the water begins to clear beyond 18". This means they are eating the natural food faster than it can reproduce.
You can use Gypsum to clarify the water. Normally it is only used in instances of turbidity caused by suspended silt and/or clay particles, This is a completely safe non-toxic application, but be warned, this can upset the natural balance of the pond if over applied, requiring supplemental feeding for the fish which, in turn, will only add to the organic load in the pond possibly triggering algae blooms.
Let me again say that an earthen-bottom pond will
never have clear water and remain biologically and chemically balanced.