I guess the best thing to do is to build in redundancies that can accommodate issues that arise. Just to share what i've done :
- ATO - Extra large volume
- Auto Feeder - trial 1 week ahead of holiday to be sure its working reliably & amount is correct
- Power failure SMS notification (iSocket)
- Backup power source - APC UPS + Ecotech battery for wavemaker
- Apex Neptune control system. Float switch in sump & display tank to trigger action in case of overflow, email alert
- OF Hydra Stream - In case 1 or 2 fishes die. Shrimps & other clean up crew will take care of dead fish. Hydra Stream will take care of ammonia spikes
- Install Toms aqua lifter to drain skimmate from skimmer cup into a separate container
- Web cam
- Pass house key to a trusted reefing friend