Ok lets get started
1- How does a person get it.
This all comes down to the introduction of anything foreign into the system. This includes water (from fish or coral bags), corals, coral plugs, rocks, inverts and macro's. These cells can NOT be seen by the human eye. All it takes is one active cell with viable DNA to reproduce.
2- How do you get rid of it
First let me start this with the basis of my answer. This is eradication not just "visible". This involves the use of either an oxidizer or an antibiotic depending on the genus involved following my thread here.
https://www.reef2reef.com/threads/back-at-it-peroxide-vrs-cyanobacteria.241002/
3- How do you prevent it
This falls in line with #1. I prepare a solution of 1ml H2O2, 1ml of an antibiotic in 2 gallons of water. ANYTHING received to be introduced into the tank gets a 10 minute bath in this even the macro-algae's.
