FoggyJ - your long term plan for this pond should be a draining and scraping or deepening the basin. You will 'limp along and apply band-aids' until then. It is the old organic deep muck accumulations and possibly nutrient enriched runoff that are affecting / adjusting the water quality (eutrophy) that are creating conditions condusive to growing duckweed - watermeal. Change the conditions and that will change what plants will grow there. Certain plants tend to be indicators of certain water conditions - we call them water quality indicators. Duck weed is an indicator. All types of aquatic habitats have them. Trout are another good common example of a water quality indicator.

Last edited by Bill Cody; 08/11/12 09:17 PM.

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