Hi! I live in NW Ohio where a majority of the ponds are 1/3a to 1/2a. They are primarily used for drinking water and recreational use. Most want a VERY clean looking pond. So while I can help them kill/control the unwanted algae, they want it GONE. Can anyone give me an general idea of how long it takes for chara to totally decompose? I understand there are multiple factors that come in to play. I'm just looking for a general idea. 1 month...1year? Thanks for any help!

Unfortunately, it usually takes somewhere between 'a long time' and 'never'. Once anything sinks to the bottom of a BOW (body of water), the lack of oxygen down there eliminates the ability of aerobic bacteria and other microscopic life to digest anything. If you have aeration going, that really helps combat the situation. There has been a lot of debate here on the forum regarding adding bacteria to a pond, in the hopes of increasing the rate of sludge decay. The evidence is unclear as to direct benefits. There are many water experts on the forum, so hopefully one of them will chime in.