The Norwegian, who had his contract terminated after the Cottagers were relegated from the Premier League, believes that the German's "strict" methods make him the wrong man to lead the club.
"Magath's very difficult to work with. He has a reputation of being a very strict manager which he is," he told reporters. "His main tool is to mentally and physically batter his players and then hopefully he gets some results out of that.
"Is that the right fit for English football? I don't think so. I thought that rather help us try to avoid relegation I thought he made things worse and harder for us.
"I hope I'm wrong because I love the club, but in a word, no. I don't think he is the right man. I think things will get worse before they get better."
Hangeland has been linked with a move to Queens Park Rangers since his release by Fulham.