dirty water: hope my story can help somebody!

first off, let me thank you for putting up and maintaining such an excellent resource for pond & koi enthusiasts. i came across your site while searching the web for information about my own problem. your Q&A was incredibly informative and gave me a tremendous jumpstart on my water garden education. please keep up the good work!

a little background on my pond: it is a modest affair...a 5' wide circular watering trough that is about 24" deep. i inherited it from the previous owner of the house (who happened to be a landscape architect!). the system was already established with a population of healthy large goldfish (started with 7 which became 11). the filtration was a laguna-type rectangular biological filter, plus it had an ornamental bubbler placed in the center of the pool on some flagstones.

my problem arose when the pond showed signs of being very stressed due to large amounts of suspended dirt in the system. the water was very cloudy and i could never see to the bottom even when the water was low. then one day my mother-in-law forced the issue when in a goodhearted attempt to help she left the hose in the pond and over-filled it all day long, thereby killing all my fish and probably my beneficial bacteria colony as well. this gave me an opportunity to do things right! (needless to say adding all that chlorine actually cleared up the water a fair bit!)

surmising that my problem was basically "dirty water" (it was not green so it was not algae) i took a trip to my local pond shop (Creative Water Gardens in Dallas, a wonderful place) to get a new filter. my old design was a top-down filter that was perpetually clogged with silt and very hard to clean. i wanted something with a better design. i opted for a 1000gal capacity laguna filter of similar design but with removable trays that held the media and mechanical filters.

after having this filter in place for many weeks the water just didn't look any clearer. i found myself washing out the mechanical filter floss almost daily and watched huge amounts of dirty sludge flow down the drain.

then one day the pond looked magically better! was my filter working? finally? wait a minute: the bubbler isn't working.....hmmm.....must be clogged........

i rooted around under the pile of flagstones to find the shoebox-sized filter box for the 350gph pump feeding the bubbler. what i found shocked me to no end: the box was completely filled with thick dark silt! i had found my problem! turns out that small box was acting quite like a vortex chamber, slowly trapping silt as it sucked in water to feed the bubbler. however, the more the silt built up the more the pump forced up through the bubbler and consequently circulated back into the pond. after clearing out the box and restoring the bubbler (and waiting a day for the system to balance and settle) the water was back to its nearly crystal clear state.

i realize that being a newbie pond owner my primary problem was ignorance. i had never really installed or maintained the entire system i inherited, so i was fairly unfamiliar with all the workings. but i never suspected the bubbler was actually the cause of all my clouding!

hope this account might one day help a beleaguered pond owner diagnose their own problem.

keep up the great site!

yours

k