Looking to make a hashtag tracking web app, running into limitations



I’m making an app where visitors can input a hashtag, and the site will track tweets and list them. Behind the scenes, these tweets are requested and cached using a cron job. The issues is, once I hit around 180 hashtags being tracked, I’m going to be hidden request limits. Can anyone think of a way around this, other than making users have to log in using their Twitter account and authenticate to add a tracked hashtag?