Terrible Idea... Your Instagram account grows authority as your followers engage with your content. If you're using bots to follow/unfollow people you aren't generating any followers who will engage with your content organically. This will lead to zero account authority and your content will never be visible in the Hashtag Search results because you will have destroyed your account. It's equally as bad to buy fake followers. If you're looking for an actual strategy to grow your Instagram channel, the best way to do it is to leverage Micro Influencers using gamification. Have Influencers earn points for following your Instagram account and engaging with your content. This will drive your follower engagement way up and make all of your subsequent content rank better because of your new account authority. And, this is infinitely scalable as opposed to using bots which destroy your accounts future ability to rank content.