It would require an algaecide, such as Cutrine Plus Granular for treatment. If you are on a waterway that connects to public water, you would need to check with your Department of Environmental Quality or DNR for any permits that are required and what chemicals that you are allowed to use.

I have also included a link to another Pond Blog question that discusses odors that are not related to Chara.

As for the fountain, they are usually best placed in the center most part of the pond if you are trying to use it to aerate, however, fountains are not the best aerators when the depths of your pond are deeper than 6′. If this is the case I would utilize the fountain for more of a decoration and use an Airmax Aeration System to aeration and circulate the pond.

Hopefully this helps.

What I mean by feeding a pond is simply limiting the amount of organics that go into the pond in the first place. For instance grass fertilizers for your lawn, grass clippings from cutting the grass, leaves & twigs that fall from the trees. These organics, once they get into the pond, begin to breakdown into “muck”, which is what we were referring to above.

Hopefully that makes sense. Thanks for the comment!

Great comment, my only thought is to keep aerating for the overall health of the pond and more importantly the fish. Other than that you are absolutely right, don’t feed the pond or keep it at least to a minimum.