Photo examples of secondary metabolites are also called myc piss, myc pee, mushroom urea. It is waste products of fungal metabolism. Not contamination itself! Immunity response of the mycelium to stress or attack of mild contamination
Yellow liquid appeared on the mycelium, mycelium turned a yellowish color, strange yellow-brown line appeared on the mycelium. What could it be? Contamination or mycelium metabolites aka mycelium piss?