In case you missed this recent thread...Here is a good example of using the Alum and Hydrated lime to clear muddy water.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=466433#Post466433...... If I use the Lime and Alum to clear the silt, can I still cultivate algae if I decide I want to set up an ecosystem so that I can feed less?
IMO clearing the muddy water will increase sunlight penetration which will actually improve and encourage growth of plankton, algae, rooted vegetation, etc.