Problem in bacterial cell culture - (Jan/28/2014 )

Do you mean I need to screen for all the single colonies on the plate and find out the one which can growth faster? 

Maybe not all, but pick maybe 10-20, and work from there.

Could the bacteria strain simply be acidifying its media or throwing out waste products that are inhibiting its own growth (eg acetic acid. lactic acid)?

Does a change in growth media help?