Hi every body

I made the ship's environment based on M9 culture media with the following ingredients( per 100 ml culture media ):

KCL= 0.2 gr

NaCl= 0.01 gr

KH2PO4 =0.2 gr

MgSO4= 0.001 gr

Fe so4 =0.001 gr

Znso4 =0.001 gr

fenol red=( 0.001 gr per 100 ml)

L-arginine= 1 gr

Why, despite the correct percentages of each of the materials, does the culture medium precipitate regularly? What is the solution to this problem?