Truth is, there is a reason for every tank "crash". Something went wrong before the tank crash, something overlooked. Corals live forever if their environment is stable and they have the proper care given. I believe most tank crashes are due to lack of proper maintenance. Everyone starts out gun ho about water changes, testing, etc. After the tank sits in the living room for a couple of years though owners become complacent about it. The thought of "oh, well everything is awesome, I won't do maintenance this week and get it next" sets in and before you know it problems start happening.
All that said, I have never had a tank crash. in the past 4 years of my current livestock of coral and fish they have been moved to bigger tanks 3 times. Went from a 20L to a 40L and now they are in a 90. Ive had ick, GHA and red slime. Ive had several fish come and go, my oldest fish being my yellow tang, 2nd being a blue/green chromis.
If you keep a notebook with your maintenance, testing, problems, etc and keep on top of taking care of your water there is absolutely no reason to have a reef for years and years without a crash. If you do have a crash, and some people will be angry for reading this, its your fault. There is no situation that can not be traced back to you at fault. Even global warming
get a back up power supply. If you are really serious about it you will have a back up system for everything. Even if the situation is out of your control, hurricane hits and power is off for days, it can still be avoided, gas powered generator, ive seen people ride out storms and keep thousands of dollars of livestock happy for weeks. Granted most tanks crash in those situations, but I have seen it work.
bottom line, its up to you how long your reef stays happy
