Another thing to think about is your house/apartment temperature.
Here is S. Florida no matter what time of the year it is HOT. And up north it is freezing. So when we go on vacation what do we do? Turn the A/C or heat off or to a money saving temperature. What does that do? Over a few days it causes you heater or chiller (if you have them) to work more than they ever have. Yes if you do the dry run you'll be able to gauge what'll happen and set accordingly. But what if they were on their last leg? And how many of us are willing to let the temp in the house swing to the extremes.
I know down here my house can easily get up to 87 any time of the year. I love my chiller but that's a big difference for my tank to stay at 79 in a house that hot. I have programmed my thermostat (81) to turn on mid day. It draws out humidity. There is nothing like coming home to a moldy smell and the walls and floors being moist from evaporation. People that have 2g-3g of evaporation a day know what I'm talking about. So IMO because your reef is like a part of the family, keep the house comfortable for it. And be sure to tell your spouse/friend/family that you set the thermostat and NOT to change it.

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I also have an auto-dehumidifier. If you have a leak, something overflows, or a spillage somewhere AND the person that was suppose to come over doesn’t, at least the dehumidifier will start the drying process faster that normal. But mainly to keep the moisture level in your house low to prevent mold, mildew... and prevent the “stinky aquarium house syndromeâ€Â.
I have a 55g barrel (usually about 30g in it) of r/o hooked up to my auto top off.
I have 2 30g tubs and 2 clean 5g buckets in the garage. One 30g tub filled with saltwater (power head in it to keep it moving and aerated). And the other containers are empty. All this for an emergency water change with the instructions
1. Turn OFF the r/o top off.
2. ONLY add the amount of water you drain.
3. Pour the water you removed from the tank down the toilet.
4. Turn ON the r/o top off.
I also have dual return pumps just in case one goes out.
Power heads plugged into UPS
For food I have a friend come over daily. What I do is place a measure amount of formula1+Formula2+a blended mixture of freeze-dried phyto & freeze-dried cyclops + top off the container with r/o into a cup sized Tupperware container. I put this in the freezer to freeze. The food settles to the bottom. When they are frozen I pop them out of the container and put them into a freezer bag. I make however many for the days I’ll be out of town (so I know if they were feed). B/C the frozen cube is smaller at the bottom (where the food is) and the nature of ice, when you throw it in the tank the food will drop into the water column verse floating on the top of the tank to be sucked down the overflow. I trust this method more than an auto feeder malfunctioning. But yes it does require human interaction.
Lights and fans are set on GE Smart home auto timer.
6g collection container connected to my skimmer’s auto drain.
Like many of the posts above have said, we invest allot of time and money in these tanks. Automation, care, and disaster recovery should always be on your mind. Leaving town for 4-14 days should not cause a conniption.
"Results are not typical. Yours may vary"