Question
I have a very small pond with a pondmaster 190 filter. Water turns cloudy after a time. I have lost all my fish after treating with pond clarifying products. I have just pumped the pond and found an infestation of tiny red/coral colored striped worms. Could they have had anything to do with losing the fish which had survived the cold winter and spawned in the spring? I need to know how to maintain a clear, clean pond before getting more fish. I have water hyacinths, some floaters, a pot of iris& arrowhead and two submerged hardy water lilies. Big problem with algae in the summer. I'd appreciate any suggestions that are not expensive.

Answer
Aside from the "clarifying products," were any changes made to the pond before the deaths?  Anything else abnormal?  Cloudy water is usually not fatal nor should the products depending on what they were.  What did you use?  The red worms are probably eating detritus (debris) and not parasites.  Parasitic worms cannot live outside the host for long.  They may be tubifex, blackworms, or a type of earthworm.  I suspect the pond was dirty enough that either the ammonia or nitrite rose, the pH crashed, the oxygen went too long, or hydrogen sulfide/methane was released from decomposition.  Did you clean the pond in the spring?  If so, then the previous things aren't the reason.  You may simply have had too many fish for that size pond.  See my algae page for info on algae.  I'm moving my site in a few weeks to fishpondinfo.com

Robyn

Pond algae page - http://userpages.umbc.edu/~rrhudy1/algae2.htm