Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants New to this pond management thing.....

My father in law built a small pond a few years ago. It's spring fed, and the water is around 55 degrees. At the damn it's about 20 feet wide, and probably goes up the canyon about 40 feet, before it becomes a little stream. This winter he started feeding the trout pellet food, and now there is a lot of moss, algae, duckweed or something else. Is this due to the food that he used? What is the best way to get rid of it.
I have read on here that you can add a couple of the white amor carp, and that would help. Will they actually do the job in water this cold?
What about this Sonar RTU, but will that work if the water is actually running over out?

Thanks for any help you can give. I will try to take some pictures and post them so you can see the pond.

I guess that grass carp would eat in such temperature but not as much as in warmer water. It won's spawn either (probably it's good in your case).
Your pond seems to be suitable for trout and if you wish to stock such fish them be careful with grass carps. Don't stock them too much as they pollute water with their shit.

Grass carp would probably struggle if your maximum temp never got above 60. Whether the feeding of the trout lead to the issues you are facing is not absolute, over feeding certainly can cause such conditions. There are other methods to control algae and duckweed. Unusual for duckweed to do well in a pond that is receiving inflow from a spring and is as cold as yours.

midget...you said moss algae OR duckweed or something else. Can you provide pics so it can be properly identified? If it is duckweed the carp wont provide much help on the duckweed and results are spotty with algae control. If it is duckweed there are a couple of other options besides Sonar RTU if you have constant flowing water. If it is just algae RTU will not kill it. If it is Common Watermeal then Sonar would be one of the recommended chemicals but it might be difficult to control especially with the conditions you have described. Is water running out of the pond all year and if so at about what rate?

So, it looks like it is actually algae. filamentous algae based on the resources here. Could Grass Carp or Catfish help? I took a temp today and it's 58 degrees, it could get a few degrees warmer in the middle of the summer. It's usually well shaded.

Should I have him stop feeding them? I think he is feeding them 3 times a week or so.

Usually it's well shaded, but one of the trees came down during a storm a few weeks ago.

We let some of the water out and pulled out most of it, but I bet it's just going to come back.

One of the things we found, were something that looked like little shrimp. Is there a freshwater version of those? Is it a good thing?

Thanks so much for the help.



Where would someone find grass carp, or catfish in southern Idaho?

Neither Grass Carp or Catfish make FA a significant portion of their diet unless they are really, really hungry. The way to combat the algae is either chemically, or get other plants in there to utilize the nutrients before the FA can.

Yes, there are freshwater shrimp, and they are good for the pond - forage diversification.

Is it a problem to use chemicals if there is some water that runs off?

What chemical is best for FA?

Cutrine or Cutrine Plus works well. But, if you have trout, you must use a non-copper based algacide such as Green Clean, Green Clean Plus or Phycomycin.

I think I might have to try Greenclean.

I have read about the blue tilapia being able to live down to 45 degrees, would they be a viable option in this pond? 58 degrees is still pretty cold.

The Blues won't be very effecient at that temp, just like any other fish, they eat the most when they are in water temp that is optimized for them. They really, really like 80°F water. It's not just the stockers that do the work, after a few months there are a huge amount of baby tilapia chowing down on the algae too, providing there aren't a ton of predators in the pond.

I am confused on the aeration approach. Why would that kill the FA?

Where did you see that statement?