Clearing Out Spam Accounts

One of my accounts has been attacked by spam accounts for whatever reason. Have only used the following method, but now everyday I get about 100 spam/botter accounts. Is there a way to prevent them from coming in without deleting my account, as well as a fast way to clear them without deleting my followers who are actually real? And no starting over isn't an option because the account is over 100k, but I got hit with for sure I know 20k fake ones :/