Bad landlord? Need help!?

Ok, my fianc� and I rent our apartment. Our drain to the bathtub is severly clogged. My fianc� tried Drano and even Liquid fire. I can't go near the stuff ( I'm 35 weeks pregnant, when he put the liquid fire in I made sure I left! ) Its still clogged so, we asked our landlord to hire a plummer. He told us to use more liquid fire! My fianc� calmly told him it doesn't work, we have used it twice now! My fianc� asked if he could use the rent to hire a plummer. The landlord told us no, we would have to still pay rent and a plummer! And the light in our bedroom is broke we asked him to hire a electrican. He stil refuses! He refuses to pay for anything! Should we call a plummer and electrain and leave him with the bill or do anything legal wise?