Septic System Inspection

Just finished my first Septic Inspection and have a few questions. I always thought the scum layer was almost fluid. The tank I just inspected it is about te consistency of quiche and about 4" thick. Is this normal? The inlet does not turn down, does this require repair? There doesn’t seem to be any significant amount of sludge. With this amount of scum is it normal for there to be no sludge?