Get used to it.

I've been keeping reefs for 4 decades and am dumber now than when I started. No matter how much I learn the sphere of what I don't know expands exponetially. The two most important things to do IMO is water changes and keeping algae under control. Third, to avoid playing musical chairs with lights which many corals don't like, is setting the lights at a set value then getting animals that like those conditions.
Here's a data bomb to both help and overwhelm. Expect any of this material to show up on the final exam.
"Coral Reefs in the Microbial Seas" This video compliments Rohwer's book of the same title (Paper back is ~$20, Kindle is ~$10), both deal with the conflicting roles of the different types of DOC in reef ecosystems. While there is overlap bewteen his book and the video both have information not covered by the other and together give a broader view of the complex relationships found in reef ecosystems
Changing Seas - Mysterious Microbes
Microbial view of Coral Decline
Nitrogen cycling in hte coral holobiont
BActeria and Sponges
Maintenance of Coral Reef Health (refferences at the end)
Optical Feedback Loop in Colorful Coral Bleaching
DNA Sequencing and the Reef Tank Microbiome
Richard Ross What's up with phosphate"
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