Welcome to PBF Paul!
In my experience, Glyphosate is effective on poison ivy. There are several pond safe glyphosate herbicides on the market. I use AquaNeat but there are many others to choose from. Just make sure you get one that is pond safe. For example, Roundup is a glyphosate herbicide but is not considered pond safe.
Good Luck!
Bill D.
Last edited by Bill D.; 02/12/16 09:25 AM.