Abstract: The arrangement includes a treatment fluid supply chamber, a first treatment chamber located above the treatment fluid supply chamber, and at least one additional treatment chamber located above the first treatment chamber. Objects are conveyed along a first predetermined path leading through the first treatment chamber and also along a second predetermined path leading through the additional treatment chamber. Treatment fluid is pumped up from the common treatment fluid supply chamber to both of said treatment chambers, and the thusly pumped fluid is discharged onto objects in both treatment chambers.