mGem: The two-decade evolution of in vivo coral microbiome manipulations.

Over the past two decades, microbiome manipulations have emerged as a strategy to bolster coral fitness. Here, we provide a timeline of two decades of research on in vivo coral microbiome manipulation studies aimed at improving coral health. A summary of coral hosts, probiotic taxa, and how experimental design varies across studies is synthesized to identify commonly used taxa and research gaps. This review highlights methodological challenges and identifies opportunities to advance probiotic development and translate microbial interventions into practical tools for coral restoration and reef management.