Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Scummy small pond connected to bigger pond advice

This is my first post here and I'm happy to have found this resource to help me in my research. I'm looking for some advice with a pond on my new property. My knowledge and experience maintaining ponds is very limited so I'm looking for any and all advice. This small pond is connected to a larger pond with some weeds/ cat tails where it gets shallower between them. The larger pond is normally very clean and looks pretty good. The smaller section is the problem and is completely covered in moss/ scum most of the year. I'm guessing its never been maintained. Looking for some advice mainly just for the smaller pond. It's probably 1/4 acre and only about 2 feet deep. I would guess the larger pond is around 2-3 acres and that one is probably 4' deep in the middle. To my knowledge, I wouldn't think fish can survive in these ponds with the cold winters we have in Iowa. I'm guessing I need to scoop all the scum off the top and put an aerator in at a minimum. Would adding some kind of tall grass, or cat tails around the perimeter help at all? Would adding a rock perimeter be beneficial? Again, I'm in the very early stages of my research and would love to hear what you guys would do if this was your property. My main goal is to clean it up and mainly just make it more visually appealing. Not worried about fish at all. However there are a lot of ducks that fly in and use the pond so I can't get too aggressive with the chemicals. Here are some pics to help show whats going on.

Keegan, I'm just a pondmeister, not an expert. They will be along shortly.

That said, if I didn't care about fish, just attractiveness, and ruled out chemicals, I'd consider two alternatives: Deepening ponds (more expensive), and biological control (tilapia for algae, grass carp for pond weeds). Of course, you would need to check for legality of stocking tilapia and or grass carp, plus make sure that you have stuff they will eat!

For me (and I am not you), I would concentrate on the large pond and confirm its depth. The small connected wetland probably would only help the larger pond by providing a refuge for young fish and forage, while helping use up excess nutrients reducing algae growth in the larger pond. The small pond's aesthetics might be improved by adding marginal plants, but they will initially need to be protected from the ducks until they are well established. Some of the marginal plants bloom very nicely. I would first try and exterminate the cattails because of their invasiveness. This would initially likely require use of a pond-safe formulation of glyphosate (like Rodeo), with follow-up spraying and/or pulling of volunteers. Wiping the a concentrated herbicide solution directly on the cattail leaves reduces chemical use but increases labor ( https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=317116 ). Giant burreed is a similar looking plant without the pitfalls of cattails. You might also keep a lookout for muskrats as they wreck havoc on many marginal plants. Trapping is the best alternative for them. If the main pond is less than 8-feet deep, and you want game fish without winter-kill, then you may want to dig it deeper. If you just want mosquito control, you could just add mosquito fish and they will likely survive. Just a few of my thoughts. Good luck!

Just a thought. How does the water flow through the property? Does it first enter the smaller pond then dump into the bigger pond? If so, then the small pond is supposed to be like that, sucking out the excess nutrients before they reach the bigger pond.

It would also likely be catching sediments before they enter the big pond if that is the case. These are both usually considered good things.

I should add that the larger pond is not my property and is part of a DNR protected nature preserve. So digging and treating the larger pond is not an option. The entire smaller pond section is on my property and I have confirmed with the DNR that I am allowed to treat and do what I want with this section that is on my property. I know this complicates things, but that's the situation. I'm not really wanting to dump a ton of money into this, but I'm willing to add an aerator and possibly add some plants/ rocks around the perimeter along with some needed chemicals or treatments. Draining and digging deeper is probably out of the question.

The water flows from the smaller section into the larger one. I get how the smaller pond is acting kind of as a filter for the big pond, but is there anyway to get rid of the scum and make it look better?

Plant marginal and emergent plants, and protect them until they get established. These plants will compete with the algae for nutrients. Water lilies are also an option, but they also need protecting initially. Mine got trimmed way back from a family of beaver before they got trapped out.

A 2 foot deep sediment pond is just what you have. Sorry, but it's not going to be easy to turn around its aesthetics without chemicals and regular maintenance. My 1/4 acre pond was silted into being only 2 foot deep when I purchased my place. The only differences were that my pond got little sun (60% of the day) and was full of crawdads...it had NO vegetation whatsoever. The crawdads kept it free of anything green. They also kept it real muddy looking. I ultimately drained it and had the 8 foot of muck dug out.

Along with RAH's advise, you could add rip-rap rock to the shore line. This will reduce the cattails in the real shallows and give crawdads a place to live. Then start adding crawdads, but only after you have a very good stand of marginals and emergents. The problem is that if the craws take off and thrive (more than you want them to) you'll have very little plant life. if any, and a muddy pond.

A nutrient laden 2 foot deep pond is going to have FA for as long as there is no controls added such as more desirable plants, crawdads, physical plant removal, aeration, carp, etc. Aeration will not be a solution all by itself. In fact, I would wait on that until later in the efforts. It can get rather costly (DIY on the cheap for $500 - $1000 for a 1/4 acre pond) and is only a small portion of the solution. NOTE: I don't want to sound like I am really advocating the crawdads. I fight them in my pond to this day. I added too many 3 years ago and have less vegetation than I'd like. They will eat the greenery if that is the goal, but there are side effects. They are fun/good to eat, however.

You have your work cut out for you. Manually remove the cattails if you don't like them and replace them with something else. Manually remove the floating scummy FA (filamentous alge) anytime it shows up. Here's a good read on the subject...

https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=523584

Any FA that you remove will reduce the nutrient load in you pond. Less nutrients = less FA.

WELCOME TO THE FORUMS! Btw

I have to be a realist here. A 2 foot deep BOW is a marsh and not a pond. There is no way you can effectively treat or control the algae that is in there unless you want to go out in a boat and spray liquid Cutrine Plus every 2 weeks. Nothing you can do will stop sunlight from getting to the bottom and that's where the algae grows.

Aeration won't help in something that shallow, you have O2 from top to bottom of the water column as it is.

You have a lot of plants growing around the edges now, it looks like it is completely ringed with cattails on the side towards the house.

I believe that 1/4 acre pond is doing exactly what it is supposed to do, catch sediment and runoff before it gets to the bigger pond, hold it there and have the plants/algae burn up the excess nutrients before they get to the other pond.

The way I see it you have 2 options.

1) Do nothing for a few years, taking all the $$ you would spend on making it pretty and saving it, with the end game being saving up enough for an excavator, semi trash pump and dozer/skid steed to be able to dig it out deeper. Put a dam across the area where it flows to the bigger pond, to keep that water there, pump out the water. Dig it deeper, getting out all of the accumulated sediment and muck that is causing the problems. Have all your plants and habitat ready to put into the pond as soon as you are done. Get all the work done to the pond, then remove the dam allowing the water to flow between both ponds again so you don't run afoul of the DNR.

2) Treat the pond with Cutrine Plus liquid, spraying the algae about every 2 weeks. Mix one gallon to 10 gallons of water. You will need to use 1 gallon of Cutrine Plus Liquid every time you treat the pond. Plan on treating the pond approximately 12 times per year. The Cutrine Plus will not affect any plants that you want to plant in the pond. With the goal to save enough $$ to dig the pond out at some point in the future. Any rocks/riprap you put in now will be a throw away when the pond is renovated, unless you pic them out of there before the work starts.

These are the comments and opinions I like to hear. Thanks! Just trying to weigh my options. I may end up digging it out one day but probably no time soon. Can I get some kind of rake and scrape the stuff off the top, along with the Cutrine Plus? Also, is there a realistic way to scrape the bottom without draining because I'm fairly sure there is a couple feet of decomposed leaves on the bottom.

See the link I posted early regarding removing FA (it shows a DIY FA rake) and pond dredging does exist, but popular opinion says that it is more expensive than draining and re-digging.

Esshup'ss realistic approach comes from a fair amount of experience...heed his advise.

You can drag a rope across the top of the pond with a couple of floats on it to help corral the FA, but when you remove it from the pond it has to be taken far enough away so when it decomposes it won't run back into the pond with a heavy rain.

It will be a LOT of work, that stuff is heavy.

I like this option to see what it does. I'm not in a huge hurry to make it perfect. Just seeing what can be done. The rest of my yard is in shambles right now anyway since we just had a new septic dug and installed last spring when we bought the house. Between dragging the FA off the top, trying some Cutrine and possibly an aerator, I'll see what happens and report back.