What do you get when you mix over 1,000 feminists with London mayoral candidates? Two men fighting for the limelight, and Ken Livingstone proclaiming that sex with someone you love is "the most amazing thing you can do" and calling to restrict over-sexualised adverts on buses.

During one of the first mayoral debates at Fem 11, the UK's largest gathering of feminists, Livingstone sits alongside Liberal Democrat candidate Brian Paddick and Natalie Bennett, the Green party's chair for women who is representing Jenny Jones. Boris Johnson has failed to turn up for the debate.

Aside from announcing a policy to appoint an equal pay commissioner if he is elected, Livingstone says he is happy to ban "bad" ads: " think actually the women's adviser and their team of staff... has got to be given veto over all ads in those areas where the mayor has direct control and I'm quite prepared to denounce newspapers for what they do."

Paddick, however, won't let Livingstone steal the limelight. He reveals he's a domestic violence victim . "I didn't understand the issues before I became a victim, I didn't understand why women went back to their partners after their partners had beat them up until I got beaten up and I went back to my partner". He is now under investigation in the phone hacking investigation into inappropriate payments to police, Operation Weeting, after admitting leaking information to the press during his time in the Metropolitan Police.

"I went on Newsnight and said that I had unofficially leaked information to the press. For example when I did the rape review, it came out very critical of the Metropolitan police, the commissioner ordered it was watered down, I accidentally sent the wrong copy of the report to the press."

The hall is packed with delegates but they aren't just here to talk about next year's mayoral election. Organised by UK Feminista, the feminist organisation set up by Kat Banyard in 2010, the sell-out conference promises to be an "important forum for generating the ideas and energy to build a feminist future" for the "burgeoning" movement. Other items on the agenda include LGBT issues, black feminism, sexual violence, abortion, and how cuts will affect women.

Manning the stalls outside? Everyone from the anti-pink project, an anti-porn men group, an anti-prostitution group and anti-female violence group - and for the woman who has everything, there are brooches in the shape of a uterus for just £3.

Inside the conference there are two ways to generate guaranteed applause; bash the Tories or call to ban pornography.

During feminist question time, featuring Liberty's Shami Chakrabarti, the Guardian's Zoe Williams, the founder of the anti-porn men project Matt McCormack Evans and writer Bea Campbell, Campbell compares mainstream porn to that featuring children.

"We should think about the porn industry affecting women in the same way we think of child-porn affecting children."

Not all attendees are leading the charge against prostitution, pornography and lapdancing. A question about why it's not acceptable to watch Debbie Does Dallas and still be a feminist is cheered.

But McCormack Evans' description of his anti-pornography position as "pro-sex" gains more applause. McCormack Evans and the anti-porn men project say they believe "you cannot have the sex industry and achieve gender equality". But pornography is a form of sex - just one the panel does not approve of.

Chakrabarti becomes a voice of reason, defending the Coalition against diatribes "I don't think thirteen years of Labour government did the trick [on gender equality] so well either."

And she urges those concerned about sexism in the media to submit evidence to the Leveson inquiry, which she promises will not be a "whitewash" ("I'm boycotting other inquires at the moment because I think they are going to be whitewashes").

Inside, a session about whether women can work together across party lines, one delegate complains the debate has not moved on since "A Vindication of the Rights of Women" was published in the eighteenth century: "We're still fighting the same fights as Mary Wollstonecraft"

But it's not all about the politicisation of pornography and the same old battles. Jo Shaw, a lawyer and former Lib Dem parliamentary candidate, says she's happy she went: "The fact that there were over 1,000 feminists there was exciting."

Shaw adds: "The upside and the downside of something like today is you get lots of people who are motivated or obsessed by certain issues but there's not some organisation saying 'we are the feminists and this is what we talk about'. But for women and men describing themselves as feminists and wanting to be active in a particular area of concern, that's a good thing."