That wouldn't be a problem with AC. First the charcoal is not harmful to bacteria or anything else that is alive in the water. In fact bacteria will sometimes use the surface of the AC as a colonizing location as it does any surface in the pond. The AC does not release toxins into the water. It does not affect algae or particulates. It functions by attracting and trapping gas molecules on it's surface in a chemical reaction called adsorption. Once it has been completely covered by those molecules it stops working and must be refreshed or replaced. You should figure out where the discoloration in the water is coming from. Stains, discoloration and odors come from the breakdown of organic materials and the release of tannic acid or tannin into the water. Sources can be mulm, fish poo, excess food, dead plant material especially oak leaves and acorns and peat moss among other things. Pebbles on the bottom trap these and make the problem worse as the debris rots. Potting soil is a prime culprit. Do not use standard potting soil for pond plants. Free floating debris in the water is a particulate. It can also produce brown water. It is controlled through an efficient mechanical filtration system.It can be any of the things that cause stains in the water or other things entirely. AC does not control particulates. Mechanical filtration does not control stains and odors. All the AC you could add would not clear the water if you have material in the water that is actively rotting. To determine if you have stains, particulates or both fill a glass container with pond water and allow it to sit undisturbed for a couple of hours. Stain will remain diffused throughout the water, particulates will float or sink.

You folks are great!! Thanks for the great suggestions! The field beside me is corn and the farmer does his spraying in the spring. But it doesn't seem to affect the butterfly population because I still see them flying over my house many times a day. I have told different people that I'm going to put up a sign that reads, 'Butterfly Crossing' because they fly the same path all the time. I have a pond nearby (with frogs-they jump into the speedwell and eat the cabbage whites) and 2 birdbaths, stepping stones for sunbathing, and full sun. I think one problem could be that the plants are not grouped together. I have for instance 2 clumps of shasta daisies in different sections instead of together as 1 large clump. I also have a birdfeeder in that area, but have never seen the little song birds go after the bf's. I've planted butterfly weed twice and each time it never came back the following spring. Oh well, I'll just keep trying things. My hubby said I can make a new sunny bed so I'm definitely going to try some of your suggestions in that one!! Thanks so much!!

I hear you all. Don't know what these crazy plants like. I have 4. 2 new ones doing well in full sun but had buds when I bought them. One gets shade from 2pm on. Nothing blooming yet. Not even a sign of it. Died to the ground over winter. The last one gets sun from noon to sunset with a break from 2-3 pm. It looks as though it may have one bud coming. It has been in place for 3 years now. I bought it the very first year they were out. Dies to the ground every winter and has never got bigger than 12 inches in all directions. I am so disappointed and stupid enough to have invested in 2 new ones this year. What are the other continuous bloomers out there? I am new to hydrangeas It may be time to consider replacing the 3 year old.

I haven't heard of Sta-Green, but if I had to guess I'd suspect the soil being too wet, or too heavy. Look up 'damping off' and see if that matches what happened. I'm super fussy with the soil I used for seedlings. I only use "pro-mix," also sometimes called professional potting mix. A few brands make such a thing, and I use Sunshine brand. They make a few different variations, such as this one: http://www.planetnatural.com/product/sunshine-mix-1/ Once the seedlings are up and growing, I sprinkle Osmacote fertilizer pellets on top to give some nutrients. Hopefully you can get to the root of the problem and get some good plants going.