I travel a lot for my real job and have to leave my system in the care of a neighbor who really knows little about aquaponics. Therefore I need to arrange my systems such that minimal regular care/maintenance is required to keep things functioning and the fish alive.
Now this is not to say I have done this perfectly. I tend to test out lots of new things and new things need fine tuning and it takes time to learn how to make them absentee proof.
For instance, the Zip Grow towers I'm testing out. I really love the idea of them. However, I have not quite sorted out a method to ensure none of them will clog during a 7-10 day period when I won't be around to check them daily.
Right now I just have the flow going through 1/2" PVC caps with a hole in them. And because the towers only want a small flow, I can't really be pushing much pressure though that line or it will send too much flow to the towers. I've tried screens or filters around the pump intake to reduce the size of the stuff getting to the tower feeds but then I need to clean the screen or the filter a couple times a week. At least that is the situation I've been running into with the 300 gallon system where the water being sent to the towers is direct from the fish tank.
In my big system my towers are fed from the pump which draws from a clean water sump and the clogging issue has not been much of a problem with them though occasionally the flow balance slightly changes over time and the near tower in the line might not be getting any water. One of the towers over the front porch system looks to have dried out during my last trip.
So, I still need to improve on my tower set ups if I'm going to keep running them when I travel.
The only other thing that doesn't seem quite perfect when I cam home this time is that there must be some debris in the main indexing valve on my big system which left it feeding only to one bed. This condition can't have been going on long since the other beds still have happy plants and no wilting so I expect that when I open the valve I'll find a small stick, leaf or chunk of something keeping the mechanism from turning as easily as it should.
Any tank feeding to an indexing valve should be as protected from solid debris as reasonably possible. An indexing valve is probably not appropriate in a gravity feed situation from a tank with fish being fed lots of plant material where stems, leaves, large seeds, sticks, etc might easily make it out the drain to the indexing valve. I've never experienced a valve clogging with fish feed or fish poo but solid objects like seeds, leaves, and sticks can cause problems.
Automatic fish feeders can make leaving much easier. It is important to under feed while you will be absent. I recommend getting the feeder long before you will be gone since it will take some time to get the timing and settings fine tuned. A feeder that has a timer that can be adjusted down to the second is a good thing so that there is no minimum amount of feed. (some feeders, the smallest feed will be like a 1/4 cup of pellets and that will be way too much in some situations.) If feeding fry, you will need to look into aquarium type feeders that can handle flake or powder feed. I have used these but most require re-setting after a battery change and the cheap ones don't last long. Most I have used are also very hard to clean!!!! High protein powder feed goes rancid rather quickly and it is hard to clean out of a little cup that doesn't open all the way up. Then you much make sure the feed container is very dry before re-filling it with feed.
Ah well. Things went fairly well with the systems over this past month when I was only home for about 5 days total.
I don't go away that often but am looking ahead to issues when I do... What I worry about so far is the water level. I need to keep the fish pool filled but there is water lost everyday and that adds up. I also like the airlines checked everyday just to be safe.
Next summer could be a challenge, I may be gone for five or six weeks. So I am trying to look for the issues now.
I have a stock tank float valve that will top up water installed in each of my systems. I install it below the normal low water level in whatever tank the pump draws from. So when the water dips below the normal low level but still above the pump running dry, water gets added. Now if it is a big pump and there isn't much space between the low water and the pump running dry, a top u valve might not be able to keep up. Like if a main plumbing pipe were to burst and the pump were just spraying water out of the system, a top up valve would not solve the problem. But a top up valve can take care of the normal additions of water or probably even keep up with very minor leaks or overflows that might happen in a system from time to time.
I like the mostly plastic stock tank float valves that are about $8-9 at tractor supply or most other feed stores. They take a hose connection and are designed to attach to the side of a stock tank. I usually install them such that a uniseal through the side of the tank will provide the sturdy object to hold the valve in place. Then I use an adapter to get from the PVC pipe to the hose connection on the valve. It is easy to adjust the length of the PVC going down to where you want to install the valve since it usually won't work to mount it on the top edge of the tank for our purposes.
As to the air lines. I have used hard PVC to get from the air pump out to my tanks on my big system so the only place where I'm dealing with the soft air line is from the edge of the fish tank down to the air stone in the fish tank. I have not found the air lines to be likely to pop off the barbs unless you are pushing more pressure/volume than the air stone is meant to handle. I've had it recommended to me to add an extra T and ball valve some where in the air system and to keep from putting too much strain on the air pump, crack that valve open just the slightest amount till you see the slightest reduction in flow to the main air stone, this way you also make your air pump diaphragms last longer since you are not forcing them to deal with more pressure than necessary.
Get a replacement set of diaphragms or the air pump repair kit for your air pump to keep on hand. If you notice a drastic reduction in air flow on your air pump, you could have a cracked housing or a diaphragm may have blown out. When I opened up my bigger/older air pump it was still able to push some air but greatly reduced from normal. Both housings were slightly cracked and one diaphragm was ripped. Had been running for over a year and they do recommend yearly replacements of those parts. Luckily both my air pumps (though two different sizes) use the same repair kit which also comes with a replacement air filter. So I can keep one on hand in case either air pump has a problem.
When going away for that long, you will want to make sure you have a friend who can be called to come take care of issues if they arise. The first year my system was running, I had a neighbor checking on things but about all he was up for was checking. So I had a friend (unfortunately on the other side of the county) who could be called to deal with any real major issues, like a pump died. He actually did get called out when a CGFI outlet in the garage failed (those circuits often don't like timers or float switches with larger pumps running from them.)
But it will be a good idea to work on an instruction and emergency sheet that you can give to who ever you have doing your daily checks. I did one with pictures even. Of course my system has changed so much now, I really need to do a new one. Anyway, for the average neighbor, you have to keep the regular duties of watching the place very very simple.