There are a few times when I have used a skimmer in a fe tank, but it's usually when something in the tank will be removed by the foaming action of the skimmer.
Usually that doesn't occur in FW, so a skimmer doesn't do much.
I'd save that if you had one, give it a try, but don't spend money on one fro FW with out a very specific problem to solve. For example I have seen them used on goldfish tanks. In that case, you have a dirty fish that throws off a lot of slime.
If you are going to get one, avoid the low price junk that doesn't even work in SW. Expect to spend about $150 - 200 for something decent.
Usually that doesn't occur in FW, so a skimmer doesn't do much.
I'd save that if you had one, give it a try, but don't spend money on one fro FW with out a very specific problem to solve. For example I have seen them used on goldfish tanks. In that case, you have a dirty fish that throws off a lot of slime.
If you are going to get one, avoid the low price junk that doesn't even work in SW. Expect to spend about $150 - 200 for something decent.