Howdy! Yes, sir — it’s always a bit of a dilemma when the seahorse keeper will be away from home for weeks at a time.
An automatic feeder isn’t an option for seahorses because they require either frozen food or live foods on a daily basis. The frozen foods would thaw and spoil in an automatic feeder, and the live foods would die and decay in any sort of automatic feeder.
The best way to deal with such situations is generally to set up a small aquarium with hardy "feed-and-forget" live foods and then arrange for a fish sitter to stop by two or three times a week and add more of the live food to the seahorse tank and give it a quick checkup, as discussed below:
When you’re going away from home, underfeeding your seahorse tank is vastly preferable to overfeeding. Your seahorses (and aquarium fish, in general) can fast for a long weekend with no problem at all. So just adjust the seahorses’ feeding schedule so their normal fast day falls on the weekend, give them a generous feeding before you leave, and they will be just fine over the weekend. But of course that’s not an option when you’re going to be gone for several days or weeks.
In that event, I would recommend ordering some hardy live feeder shrimp, some of which can safely be added to the tank every couple days, knowing they will survive in the aquarium until eaten. Ocean Rider’s red feeder shrimp (Red Iron Horse Feed, Halocaridina rubra) are ideal for this as are the post-larval white shrimp (i.e., "snicking shrimp") from Seawater Express. They are what I’d like to call a "feed-and-forget" food. They are tough, rugged little shrimp that you can toss in your tank with no acclimation whatsoever. They are agile and elusive enough that your filters won’t eat them and the seahorses won’t be able to capture them all right away. Some will hide and evade well enough that your seahorses will still be hunting down the stragglers for the next day or two. Best of all, you can toss a nice batch of them in your aquarium, secure in the knowledge that they won’t perish and pollute it, but thrive and survive as real, live, "catch-me-if-you-can" prey items that seahorses cannot resist. Nothing stimulates a seahorse’s feeding instinct like the frantic movements and evasive maneuvers of natural, living prey.
So if you are planning on being away for an extended period of time, Tom, I would suggest lining up a supply of suitable live foods, and setting them up in a small tank of their own with a small algae-covered live rock before you leave. Even adult brine shrimp (Artemia spp.) will do for this in a pinch. That way, when your "fish sitter" checks in on your aquarium every so often, he can just add another netful of feeder shrimp to the tank and that should take care of your seahorses’ feeding requirements until he stops by again.
Aside from adding the live shrimp, your fish sitter’s duties will be extremely simple, mainly just checking to see that everything is operating properly. Power outages, equipment failures, or the untimely death of a specimen can wipe out your tank if they happen while you’re away. Consider recruiting a friend, neighbor or coworker to look in on your tank at least a few times while you’re gone. They needn’t be aquarium savvy at all, since you will be assigning them only the simplest of tasks: (1) check to see if the equipment is on and operating properly; (2) add freshwater to replace water lost via evaporation; and (3) toss in a netful of live feeder shrimp. And that’s all. In fact, it’s a good idea to forbid them to touch anything or do anything other than those 3 very basic duties. And, of course, you will be familiarizing them with your setup beforehand, leaving them a plastic gallon jug of dechlorinated tapwater or RO/DI water with which to top off the tank, and providing a supply of live feeder shrimp and a net so all they have to do is scoop some of the shrimp and dump them in the tank. (Stick with the live food if you recruit a fish sitter, Tom. That way they won’t have to deal with preparing frozen Mysis and there’s no danger they’ll overfeed it. I learned the hard way that inexperienced seahorse keepers ALWAYS have a tendency to grossly overfeed, but that’s not a concern with live feeder shrimp.)
The live feeder shrimp from Seawater Express are easy to care for and would be another good choice for this. They provide bite-sized white shrimp (Penaeus vannamei) in batches of anywhere from 50 to 1000 each. They are hardy, easy-to-keep and disease free. I recommend getting the smallest of the "Snicking Shrimp" they offer in order to tide your seahorses over until you get back from your vacation:
Seawater Express Inc.
Organic Shrimp Farm / Hatchery
Small ghost shrimp, live Mysis, Gammarus amphipods, or even good old adult brine shrimp are also useful feed-and-forget foods for the seahorse keeper who is taking a vacation.
Another option would be to hire a local aquarium maintenance business to service your seahorse setup a few times while you’re gone. Having professionals service your tank can be expensive, Tom, but it shouldn’t be too costly as long as it’s just for a few service calls on those rare occasions when you’ll be away for an extended period, and it’s mighty reassuring to know your fish are in good hands. Might be worth it to have that peace of mind.
All kinds of different objects will make a suitable feeding post or feeding trough, Tom. The following link will take you to a site with photographs of different types of feeding stations that seahorse keepers have devised to give you a better idea of the possibilities in that regard:
You can also buy ready-made feeding stations if you feel that would be easier than improvising one of your own. For example, the Aquarium Fish Dish sold here works well in some seahorse tanks:
Or better yet, you could try the following feeder that was designed specifically for seahorses:
Best of luck with your upcoming trip, Tom! Good luck arranging for a reliable fish sitter to check up on your seahorses two or three times a week while you are away.