?Follow/Unfollow – total actions per day ( 2017)

Hello, I'm wondering what are the total limits (for follow/unfollow) of the daily actions? Anyone got idea?
I follow & unfollow manually 450 accounts per day, total 450+450 = 900 actions.
Is it risky?
Is it better to follow 450 accounts in one day and the next /other day, to unfollow 450?
Let me know guys because in the last days I have noticed some problems with the hashtags. :(