Holy crap - 9000 users total and pages of new registrations in 1 day, including someone advertising cheesecakes online at this very moment. Reporting by hand would be completely useless against this flood. The moderators should have a "delete account" button on the user list, so that they could look at the website address and 1 click delete if it looks like advertising. Adding a column for last active date would also help - it would be much easier than running a python script to fetch each user's profile individually just to extract it from the html.
You seem to have cleaned up to about April 7 (page 42 sorted by registration date descending) but you missed 14750 and 14764 (dating tips website).
For the math captcha, have people solve for a, b and c such that a^3 + b^3 = c^3. That'll get rid of the damn bots.