Answer this ??

Dear student,

Methanogens belong to Archaea and are anaerobes that produce methane as a by product. They can grow at extremes of temperature, pH, and salinity. 
Although they are taxonomically diverse, they use a limited variety of simple energy sources.
Thus, growing or culturing these methane producing anaerobes is easy and can be achieved using the following energy sources-
substrates such as
1. H₂/CO₂,
2. acetate,
3. formate,
4. methanol and
5. methylamines

The most important of these are generally H₂ and acetate.
Regards