Pond weeds

Our pond water has cleared up in the last couple of years, and we have a lot of weeds and water plants (no hydrilla). The neighbor has the same problem. He says he’s going to put weed eating fish in there. We’ve used chemicals from The Pond Guy for a couple of years, but it hasn’t really done a great job. I’ll see how his fish work out before I do anything.

What have you guys done that works - fish or chemicals?

Fish.

Do you ever plan to eat anything from the pond? Ever swim in it?

Grass carp are a more cost-effective and long-term solution to vegetation control but they don't eat everything. Tilapia can work well on filamentous algae. Goldfish can work well on duckweed/watermeal. Would need a positive ID on the plant community (all the species you can find) to be certain whether a biological control would help. Would also need some details on the pond too; size, depth, species stocked, management goals, etc.

Chemicals work great when you know what plants you are treating, select the proper chemical, and apply it correctly. One big problem with chemical treatments is that while they kill the plants, they don't address the reason the plants grew in the first place (nutrients and light availability). So, when those plants decompose, they release their stockpile of nutrients back into the water to fuel the next generation once the chemical concentration fades to non-lethal levels. As long as there is good light, nutrients, and water, plants will grow.

You could consider an aquatic dye to reduce light availability. This doesn't kill plants, but it slows them down in water deeper than about 3-4 feet. Lasts for several weeks to several months depending on the brand and hydrology of the pond. Have to keep an eye on the color and reapply when it fades. Won't really do anything to shoreline emergent plants but it will slow down submerged plants like coontail, milfoil, hydrilla, naiads, pondweeds (potamogeton spp) etc.

You can also extract some nutrients by physically removing as much of the weeds from the pond as you can. Drag them onto the bank, let them dry for a few days, then haul them outside of the drainage to the pond so that they don't get washed back in. Obviously this is a huge amount of labor, but short of draining the pond and excavating the organic load there's not much else you can do to actually take plant-food out of the pond.

Think of it like a garden. Even the best-designed gardens are going to develop weeds over time and they require attention to keep nice. Do a little bit every day/week, or a huge bit every few weeks/month. Ponds are no different.

Scott,

Well said. Good advice.

That’s a lot of good info. Thanks. I’ll have to give some thought to what fish to use. I’d prefer to not use chemicals. And one thing I have been doing is raking out large amounts of those plants. It is a lot of work.