Election 2015: Farage and Bennett on voting reform

Is a system which allows UKIP and Greens to get five million votes between them but only one seat each, fair?

Compare that with the SNP who got 56 seats from 1.5 million votes.

Speaking on the BBC's Victoria Derbyshire programme, former UKIP leader Nigel Farage, and Natalie Bennett, the leader of the Green party, both agreed voting reform is needed.