Originally posted by shinglhed:
I have about 1/3 acre pond about 6' deep stocked with rainbow trout. Before I bought the property the water was clear but all summer now has been very murky. The pond is cold water and fed by two natural springs. One flows down a small stream into my feeder pond, the other is tapped and has an underground pipe running directly into the pond. I cleaned out most of the feeder pond earlier this year and got the pipe flowing again but the water in the pond is still a murky green/brown even though the feeder pond is now clear. The pond has a natural clay bottom. I've been doing some research on the net through newsgroups and different bulletin boards and am getting a LOT of different views. One local farmer around here says he'll give me some fresh water mussels from his pond and they act as filters. The research I did on mussels says that during their larval stage they are a parasite to fish but are generally harmless. But it doesn't tell me what fish they are harmless to and they need specific types of fish to propagate but they don't say which kinds or which kinds of mussels I should actually use. Some of the other advise I've gotten is; to use gypsum on the water, to try adding alum to the water, add some grass carp to eat up all the algae, use chemicals from a pond store on the water. Before I go any further I was wondering if you had any advise or outlooks that might help with this problem? Although the mussels seem the most organic treatment I'm hesitant to introduce any new species into the pond especially as they could end up going down stream into other waterways as well. Thanks.
Shinglehead,
Small fry gives excellent advice and I too agree if your fish are healthy, you may just want to take a wait and see approach.
I too have a trout pond (maybe two if I decide to utilize another pond)
Be aware that phytoplankton (suspended algae) can be greenish/brownish in color and mimic clay turbidity. You could hire Bill Cody to sample some of your water to see if it's suspsended algae or you are looking at or clay particles. Not only could you have stirred up clay particles when you cleaned out your feeder pond, you may have stirred up nutrients that caused your phytoplankton to increase in number. As was stated in the previous post you may want to determine if there is any reason for increased nutrients. Feeding more feed will do it too.
My present trout pond has a murky greenish color most of the year due to a combination of iron in the well water that feeds it, and a mild algae bloom. Once it gets cold enough in late fall I shut off well flow and the water clears dramatically. The mild algae bloom does not hurt the fish and in fact shields light levels keeping submergent weed growth down.
I am presently filling two ponds with well water and initially they are brown from the iron which looks like silt at first (no significant rainfall and incoming silt), but in a few days after filling the iron settles and the ponds turn an emerald green.
If you want to try and settle clay particles if that is the cause alum will take care of that. In the right quantity it will be safe for your fish if your water is hard with high alkalinity. If soft go with gypsum. If you use either you will have to test the water to see how much you need if you go this route. Here is a site to go to, to explain how they work and how much to use:
http://agfacts.tamu.edu/D11/Calhoun/Mar/Recfish/Pondmgt/mudpond.htm
