freshwater baths

[George]

I have been doing fresh water dips for years, although not to treat brook. It's a good and quick way to reduce external parasites from fish. (key word is reduce. You still have to treat remaining whatever parasites the fish has).
The link you have is a good start to do the treatment. Basically you just need to match PH and temp to your DT/QT as much as possible. The only thing I do it differently from the link is I only do it for 5 min. max. I believe that if parasites can withstand a freshwater bath for more than 5 minutes, it's very likely that they can withstand 30 minutes.