I need to know if a tax exsists for those coming to us from Nigeria.BTU?Tax?

I have a person wanting to visit from from Lagos Nigeria,he said that he must have 1,300.00 to enter united states.I believe it is called a btu tax.I am not sure if that is correct term. he said the money is not turned over to customs. It just shows you have form of income. does such a policy exsist?