Like many other torrent websites, TorrentGalaxy is illegal in the majority of countries if it is used to download copyrighted content without authorization.  Magnet links make it easier to access the files, even when the website itself might not hold them.  This may result in infringement of copyright.  Using the website to download or distribute copyrighted content without permission is usually prohibited, though legal repercussions will vary depending on your rules.  Make sure the content has a free-use license or is in the public domain before torrenting it legally.