- Joined
- May 14, 2018
- Messages
- 567
- Reaction score
- 519
- Location
- St Augustine
- What state or country do you live in
- Florida
One proposed mechanism for what caused OTS can be thought of as a complex, self-feeding chain of events. What is known is that an increase in nutrients alone doesn't kill coral. However, high levels of DOC does. High nutrient levels tend to fuel algae growth. Algae release excess photosynthate (DOC) into the surroundings. High DOC stimulates the coral's resident microbes to reproduce rapidly which uses up the local oxygen. So, basically, in this scenario the corals suffocate. On top of this, high DOC also fuels microbial life in the environment, including pathogens, that negatively effect coral. So coral's die releasing more nutrients, fueling more algae/microbes...and things go from bad to worse until the system collapses.
IME, replacing a sand bed in a properly maintained reef aquarium is not necessary. I have a sand bed that is now over 20 years old and has been in two long term systems.
My sense of worry is fading now thanks to this. For a short time, my concern was growing, since my reef is in the sweet spot between established and mature, that the end was coming.


