The reason for such low growth rate is due to the fact that 4 antibiotics are need to be included in the culture. Kanamycin, tetracyclin and chloramphenicol for the host and ampillin for the plasmid (if your plasmid confer ampicllin resistance).
do the antibiotic concentration correct?
I use 100ug/ml ampicillin, 50ug/ml kanamycin, 35ug/ml chloramphenicol and 35ug/ml tetracyclin.
Under this growing condition, i can get average size colonies after at 24hours.
School of Life Science
The Chinese University of Hong Kong