# 271: ACIDITHIOBACILLUS (APH) MEDIUM


## Main sol. 271

2	g	(NH4)2SO4	
0.5	g	K2HPO4	
0.5	g	MgSO4 x 7 H2O	
0.1	g	KCl	
0.02	g	Ca(NO3)2 x 4 H2O	
8	g	FeSO4 x 7 H2O	
1000	ml	Distilled water	

1. Dissolve ingredients and adjust pH to 2.0 with 10 N H2SO4. Sterilize the medium by filtration. Alternatively, autoclave separately the basal medium (pH adjusted to 2.0) and the ferrous sulfate (8.00 g FeSO4 x 7 H2O in 50 ml 0.1 N H2SO4, pH not adjusted, in a sealed vessel under nitrogen gas atmosphere).
2. Note: Incubate statically without shaking.