There are a lot of diy methods for unclogging drains. The easiest method is to just flush the drain with boiling water. What I normally use is a mixture of salt and baking soda.Take about ? cup of salt and then about ? cup of baking soda and then pour it down the blocked drain. You could use baking soda and vinegar or even bleach. Here?s a blog that mentions some safe chemical free diy methods to unblock your drains(http://www.brothersplumbing.ca/blog/unclog-drain/6-ways-unclog-drain/).