带有form_tag的错误消息在单独的控制器Rails 3中

I used a form_tag to access an action from a different controller in one of my Rails views. This has caused trouble for me rendering the error message. I am also using JQuery which could potentially be causing an issue. I have read that form_tag is not bound to a model, so that might mean that something like validates_uniqueness_of might not work. Would appreciate help understanding validations with form_tag!I used a form_tag to access an action from a di