I am no expert nor do I want to ride on a high horse here but come on.
Seriously corals are sensitive. That is the reason why saltwater reef tanks are one of the hardest hobbies to partake in. Read the board- look at the issues people run itno- think about the while idea of keeping these very sensitive wild creatures that we know very little about in a small ecosystem that can hardly mimic the ocean.
The smallest things can cause corals to react. New water, new flows, changes in lighting, changes in PH, changes in salinity, changes in temperature, ect. ect.ect.
Everything affests the tank and the corals. Don't worry about it just read, learn and use the board as a stepping stone. If you keep your tank at the right levels and do your PWC then you should be ok. Sit back watch and enjoy. YOu will learn the small things are normally not a big deal.