I’ve seen leeches always as the hardened sludge at the bottom of the Apprentice barrel. My leeches are horrible (around 600 in total as I’m writing this), and my apprentice leeches are still swinging between 20 and 40. If you must reduce your leeches, take a break from lessons and focus on those. If you want to steam ahead, look at what apprentice count you can take and just add lessons according to those.
Don’t mean to promote my own scripts as well, but some leeches are kind of permanent. So your leech count can be kind of scary sometimes while you can’t really do anything about it. My script lists all your leeches, counts them, and shows how many are “burn-only” leeches, meaning they only go away when you burn them finally.
Of my current 617 leeches, I have 242 that I can only remove by burning.
In the mean time, a large amount of leeches has been going up the ladder 
