I would contact a lawyer. That photo looks pretty bad. It seems like there is a leak within the wall. They drywall needs to be replaced as well as the pipes and connectors. You should call a lawyer that can help you discuss the landlord's obligations. I just started following this lawyer on HP, but I don't know if this is his specialty; maybe you can ask for his advice: http://hubpages.com/@aaronhicks Hope this helps!
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