Using microorganisms for bioremediation and metabolic engineering becomes popular in times of declining amounts of petroleum. Even though many organisms could be successfully engineered, a high metabolic burden and a lack of evolutionary stability remain. Therefore the usage of synthetic engineered microbial communities is under investigation as a potential solution. One challenge is the control of growth of each of the populations within the community. In order to balance the growth in a mixed synthetic E. coli community, we propose two growth-balancing systems: one is a quorum sensing system, the other one is a contact dependent inhibition system.