Ive got a pond that i built little over 20 years ago and have got a problem with algae and submerged weeds. I've tried mechanical raking and using grass carp but doesnt seem to be improving not real crazy about using chemicals but thinking I may have too unless someone has a better solution.

Have you also looked into reducing phosphates and nitrates into the pond. Malfuctioning septic systems and ag runoff can be a problem.

I had an issue like that. I gave in and purchased and algicide from Amazon. It worked great. Got rid of all that green slime crap within a few days. I then added a fountain (a pump on a weighted bucket). Keeping the water moving as well as adding blue dye to the pond keeps the algae away. I only have issues when the geese are in the pond during the mating season. I guess all that nitrate form their droppings is like algae fertilizer. I put the algicide in a sprayer and start spraying the algae clumps that gather around. its gone in 2 days. .

One word....copper

That's the main ingredient in any submerged weed herbicide ive ever used.

Had a friend that would chop up old copper pipe and wire. Some he would then smash with a hammer. Put it in a nylon mesh bag and toss in the pond where he wanted weeds to not grow. Other bags he would stake down at the water line upwind just submerged. Trace particles would kill the weeds in the drift zone and also killed the algae that floated on the surface. In two years time the change to the pond was remarkable. No harm to fish frog snakes or muskrat that we ever saw. Cheap and easy to do. Most people have scrap pile laying around. If not go to a scrap yard and buy some

Trying to minimize N, P and K in a pond is very difficult. For example it takes 30 units of P to grow an average or say 160 bushel corn crop. In the liquid situation of a pond it only takes a fraction of the 30 units like 3 or so to get very high levels of vegetative growth. The natural amount of P and even N and K in your area are probably more than those amounts. Chemicals such as mentioned will do that but will also change the whole biology and habitt of your pond.

B ryce

I know a guy that used the herbicide for grass control, and had for several years, then something went wrong and killed all his fish so he’s not using it anymore.

https://a.co/d/0blPl9nQ

This is great for that in a pool. Not sure about a pond w/ fish but you get the idea.

Note that algacide kills the algae. Phosphate remover removes what the algae eats so they are both gone.

I believe its common to spray ponds like that with copper sulfate. Copper sulfate is just an algacide.

Soil here is naturally acidic.
If I were to try and manipulate my pond.
First try would be PH change with lime.
Second try would be placing whole alfalfa bales.

Copper sulfate for algae and weeds, Aluminum Sulfate for phosphorus and clarity issues. Texas A&M has some good resource information….

Supposedly, pond dye will reduce algae growth. I have algae in my pond and the dang ospreys and eagles are enjoying fishing in my pond’s clear water. I am thinking of trying some pond dye. Might contact Pond Boss or Others that specialize in these things

My pond - a lot of algae and clear water

Better stick to chemicals designed for pond use. A fish population that took years to develop can be gone over night if your not careful.