Before revision:  We show using an eight species community that this is an efficient and robust method for computing dynamic flux balance analysis simulations, and so is capable of simulating communities URLanisms. We demonstrate that the method gives an approximately 85 \\%DIF < speed-up URLanism over the standard and widely used method.
After revision:  We demonstrate the efficiency and robustness of our method by comparing with currently used methods on a four species community, and show that our method requires at least 91 \\%DIF < speed-up URLanism over the standard and widely used method.