Over the last year-and-a-half, organic reach of brand or fan posts have dropped significantly. Some reports claim it to be below 5 percent. Brands that spent years building out their Facebook following are now seeing their organic reach fall significantly.

Facebook has said that this is due to changes made to the algorithm that determines what content is shown. With the promise of viral marketing on Facebook now slipping away, what is a social marketer to do?

Related: 4 Tactics for Surviving Facebook's Algorithm Changes (Infographic)

Post frequently and optimize. This option can be a very effective for advertisers who have great viral content to share. Currently, the Facebook algorithm boosts reach for posts that include images and/or links. Including links can give marketers up to a 30% increase in organic reach.

Keep track of what you post and optimize based on the reach you get. It is still possible to get significant reach if your content is widely shared by users.

Leverage other social media platforms. Facebook is not the only social media platform out there. Brands on Twitter will still get 100 percent organic reach, with everything you post. If a large number of users “retweet” your content, it can dramatically increase reach.

Pinterest and Instagram can be great for retail and fashion. YouTube and video sharing sites like Vimeo are still effective for viral brand video promotion. SlideShare and LinkedIn work well for reaching a professional audience.

Content syndication. Orignially, these platforms emerged as a way to increase traffic for blogs and content sites. But they can be leveraged by marketers who develop lots of high quality content. It works in a similar way to an ad network but instead of buying ad space, you buy a content promotion slots for a blog post.

Syndicating top blog content can dramatically increase your site traffic. Try leveraging multiple content syndication networks such as OutBrain, Taboola or RealGravity to maximize reach.

Related: Facebook Is a Fundamentally Broken Product That Is Collapsing Under Its Own Weight

Use promoted posts on third party viral sites. You can hire sites like BuzzFeed.com and EliteDaily.com to create and promote content that has a much better chance of “going viral” than what your team could create.

These sites specialise in creating highly engaging content that can achieve significant virality across many platforms including Facebook. Skeptical? Here is a video they created for GE, an iconic American brand. It’s received more than 900,000 views on YouTube.

Retarget users through the Facebook Exchange (FBX). The open architecture of FBX allows a select group of ad techs to buy some of Facebook’s advertising inventory. To access those platofrms, search for an ad retargeting vendor that allows you to create “segments” of users based on the pages they visit on your site, then target them with ads on Facebook.

This option may not expand your audience, but it will help you maximize the value from the traffic you already get.

Pay for Facebook ads. Unfortunately, this is the best option if you want to reach your audience on Facebook. However, paying for advertising on Facebook does have some advantages.

It’s still relatively inexpensive when compared to paid search on Google AdWords. Paying for ads also opens up a host of audience targeting features, and could actually improve the quality of your Facebook marketing.

Related: Is Facebook Advertising for You?