So, I definitely need some help. I'm having a major aquatic plant/algae problem and need some help with how I should address it.
For a little bit of background, my pond was dug in October 2016. Most of the soil is clay and sand, but the area where the pond was dug was in a low-lying wooded area that previously held water, and the excavator was pulling up logs 10-15 feet under the ground, so I'm guessing it was a swampy area for a long time.
I did not start seeing any type of aquatic plants until around February of this year -- small patches of basic pondweed with small leaves floating on the surface above strands that ran to the bottom. Over time, those patches have grown into many large clumps. ( see picture ), but it seems like algae is also growing and clumping on top of the pondweed.
I stocked the pond in May, and I'll say that my fish are doing extremely well. The bream, bass, and channel cats are growing very well, and if I could manage to get rid of the huge masses of bullhead cats, things would be great - fish-wise. I haven't seen a single dead fish, and their rate of growth has really surprised me, but I'm concerned about all of this plant/algae growth affecting oxygen levels. I will say that the fish did like it with a little bit of plant growth, as it gave them some cover and shade from the hot Louisiana sun, but things have just gotten too far out of hand. I feed a mix of pond fish pellets and dried mealworms about every other day. I don't think I'm overfeeding. Between the bass, bream, and the huge numbers of catfish, every single bit of food is eaten within minutes.
Now, it appears that in addition to the pondweed and algae, there is something else taking over the bottom of the pond. I've used a rake to pull up some of it. It tends to fall apart into pieces, and it has an odor almost like onions when you pull it out. Here are some pics of it in the water, and out.
So, my questions are:
What is it, and what can I do to control it? Like I said, it hasn't had a negative affect on the fish ( either those that I've stocked as fingerlings or a few that I've bucket stocked ), but my pond is not huge, and this is starting to take over a considerable area.
Any help would be really appreciated.