Microalgae media - pH adjustment - (Dec/17/2011 )

I am just curious about whether you adjust the pH for microalgal liquid media before or after autoclaving.

I generally adjust it afterwards , since the pH tends to increase drastically during ac. This is quite cumbersome as I need to pay extra attention that the medium does not become contaminated while adjusting the pH.

I am not sure what is the most appropriate way to go about it... your suggestions would be greatly appreciated.

Take an aliquot of your autoclaved culture medium, and adjust the pH, keeping track of the amount of acid or base needed. Multiply by the ratio of aliquot to medium size, and adjust the medium in one step.