ok,let me help you to figure it out.
if you are encountering a 'WALL' on buy order or sell order,the first thing that you need to do is observing the wall itself and how long it maintains its place on the order.
usually if it was a real one,it will stay still even after half of it get bitten by people.
(sometimes it will disappears after it get bitten by people for a half,and appearing again after it hits a new low in the future)
on the other hand if the 'WALL' acted like a ninja(appearing and disappearing),this wall will act according to the market and won't maintain its place if it get bitter for more than 10% from its original orders.