I am thinking of partially finishing my basement by painting the walls and carpeting the floor. We have a sump pump and walls luckily do not get damp. However, the basement wall is a concrete pour, so is not smooth. I sample painted a portion with regular paint (left over from painting dry walls). The paint is not even small pores in the cement are not covered, what is the best paint to use for this situation. The wall is about 5 years old.