While only a tenth acre size, lined, 0.4 acre-feet, four years old, aerated, treated with bacteria, and well fed, in August my pond was suffering a massive bloom after I removed hundreds of pounds of wet sunken leaves and mucked the sediment out (which must have liberated phosphorus). Don't expect a bottom muck eating bacteria to eat last fall's leaf fall or even the previous year...they do start to de-compose, but don't lose their shape (I now realize I must put my sein across the south end of pond to catch the leaves almost daily for several weeks...live oak and pecan). After a shot of cutrine plus, the water got to looking better but not great, still cloudy and only 18 inches visibility...Dangit all, I expected a clean and clearing pond after three weeks of mucking work (the leaves kept plugging the vacuum head, which went thru various design changes, until we removed the leaves). I then tried some polymer flocculant products, which helped clearing but still left a cloudy state. Got ten pounds of pure alum to play with...saw some interesting effects in buckets of pond water...a few crystals of alum would drop out everything, perfect clarity, but then half the floc would float to the surface...add a little polymer flocculant and all would drop to the bottom. I calculated I would need about 120 pounds of alum. Hmmm...I saw that alum consumes more than its weight of minerals providing alkalinity and even though we have hard water with good alkalinity I don't think my water can provide hundreds of pounds of alkaline minerals. So, there it was...want to use alum, get the hydrated lime. Then I found Phosclear, forty pound containers that appear to be about half alum and half alka seltzer (sodium bicarbonate), a buffering agent. The Phosclear info gives the weights required for either phosphorus capture or water clearing (twice as much). At $120/container, I can afford this "safe" product only because my water is small. Well, after sixty pounds of Phosclear plus the ten original pounds of alum I threw in (I think a total of forty pounds alum), the water looks really good...sechi disk two feet...and we can see the fish. I have another twenty pounds to play with. Can alum treatments work cumulatively? I don't know, but I'd like to know. I am intending to keep using Phosclear treatments.
Something else conundrum: Fish kicking up dusty sediment. I'd like to sequester it. I found a lot of muck was somewhat cemented...I've been using polymer flocculants for years...wondering if the polymers provide some cementation. I also saw a post here that a fellow's sandy beach had cemented nicely after an application of Soilfloc to stop leaks.
