In the present study, microbial communities of sponges, Sediments and Seawater inhabiting coral reef ecosystems were investigated using barcoded pyrosequencing of 16S rRNA gene amplicons. Our main goals were to compare the bacterial and archaeal richness and composition of two sponge species, sediment and seawater inhabiting coral reef systems. FLX 454 titanium pyrosequencing study. Note that the sequences submitted are raw sequences prior to any analysis and thus contain short sequences, poor quality sequences and chimera. These will need to be filtered out using, e.g., using qiime scripts such as split_libraries and pick_otus with the usearch_ref argument, which will provide a chimera check and filter out poor quality sequences.