Use thirty hashtags/post, but do not over-use the same set of thirty.
In Instagram, if you use the same hashtags and many of them, on all/most posts, you will very likely get shadow-banned. Instagram will stop letting your posts get found through search, so you’ll get less likes, less follows and less desired actions. Counter this with saved research: RiteTag TagSets or, use the RiteTag browser extension, right-click on image, and use the Get Hashtag Suggestions option to get hashtags for each of your image uploads. This works in Later, Buffer, Hootsuite (search Instagram in our help; your web-to-Instagram solution is probably one of our intergrations) and over 15 web tools that do web-to-phone notification scheduling.
Make TagSets by either using the RiteTag extension and right-clicking on an image > Get hashtags for Image. Or, Open the RiteTag Hashtag Bar by clicking on the RiteTag browser button and then use the left side image button to get hashtags for any image in your computer. Open RiteTag and at the bottom, paste them, save a TagSet. Now you'll have more variety in your hashtags, and Instagram wants this; hashtag spam is what they're cracking down on with shadowbans.
See the full RiteTag Extension tutorial for more.
Also, you can do research with RiteTag (https://ritetag.com) and create TagSets based on your research on the site. Use the interactive analytics, with a sphere of hashtags in which when you click outside the center, you get analytics (Twitter-based, but there’s overlap of results in Instagram for most of them) on the hashtag in the center. Click the bookmark icon to send the tag to the bottom if the numbers look good (high engagement and shares vs. uniques, which are your competition). Try with this analytics page: 30 growthhacking hashtags popular on Twitter (https://ritetag.com/best-hashtags-for/growthhacking).
Remember to make a TagSet for each topic you tend to share posts on or, variations of the topic. If you continually add the same hashtags to many posts, you will probably get shadow-banned, and thus, your posts will not come up in search. This is death to likes, comments, shares - all the interaction we need in Instagram. Prevent this by doing the RiteTag research once, make TagSets on many topics, use them with appropriate posts.
Since there’s so much overlap of hashtag engagement between Twitter and Instagram (but not as much with Facebook), RiteTag is what you need. When you've done the research, though, save it, per topi, in a TagSet, for access in the RiteForge Android app and the mobile-friendly RiteTag site. Your TagSets are right on the RiteTag Dashboard, when you're signed in.
Remember, it’s all about relevancy and engagement potential, and this changes for hashtags in active use. You’ll need to check how a hashtag is doing, but there are shortcuts.
Also see: How to setup RiteForge mobile application for Android