How to build your own formicarium (cheap!)
You will need:
Substrate, landscaping, paint.
I love keeping ants. They’re low maintenance, fun to watch, and a fantastic teaching and outreach tool. Kids and adults alike get excited to see the inner workings of a functioning ant colony, complete with queens, workers and brood. And fortunately, there are more and more resources available to the amateur ant-keeper. Unfortunately, some of these resources can cost you a bundle. I have embarked on a quest to make my own custom formicarium as cheaply as possible.
In particular, I wanted to make a formicarium that was attractive, easy to manage, space-friendly, and easy to transport. I love the flexibility of set ups with tons of tubes connecting various nests and outworlds but these are a tricky thing to juggle when heading to a school or outreach event. Altogether I spent less than $40, and a good chunk of that was on reusable supplies. (I can make MORE– BWHAHAHA!)
That said, this was my first attempt, and it has been a learning process. I hope this will be of help to others. This formicarium design is easy to modify to suit your own needs, so I highly recommend taking some time to browse Google and websites such as the AntFarm (forum), AntStore, and AntsCanada for tools and inspiration. If you do make your own formicarium I’d love to hear your stories and see pictures!
You can also check out my collection of more formicaria designs and suggestions.
First, find a good size container for your ants. I chose a large sized plastic terrarium from the pet store. (This is cheap and light weight, not quite as bulky, and comes with a lid.)
Next you will need some supplies to cast the nest. I bought 3lbs of cheap plaster at HobbyLobby. You could also try something a little sturdier like HydroStone or Tuf-Stone. You want the material to be capable of absorbing water (most ants need high humidity) but mold resistant. (Plaster will mold. Low levels are unattractive, but not particularly harmful in my experience.) You will also need something to make a mold from–I bought a cheap tub of clay. Play-Doh, putty, whatever would probably work.
Line the areas where the plaster will set with plastic wrap so that you’ll be able to remove the nest casting once it sets. Try to get the plastic wrap as smooth as possible, as wrinkles will show up in the final version, and might even provide unwanted crawl spaces for ants. Something like waxed paper might also work, as long as it fits tightly against the container surface.
Now you get to the fun part. Using the clay, design your ant nest! Make large chambers, small chambers, connecting tubes, etc. Run one to two nest entrances perpendicular to the container wall so that they will stick out of the plaster when it is poured. Don’t forget to leave 2-3″ of space at the top for a vaseline band around the container to keep ants in! Using modeling clay, create a sealed lip along the top edge of where the nest will be to hold in the plaster. (If you angle this lip so the top of the plaster nest slants toward the outer wall you’ll have a nice little catch dish for watering the nest later.)
Smooth the edges down as you work so your chambers won’t have curved in edges, hiding the ants from view. It’s also a good idea to give chambers a slight slant so that the ants can use a bit of gravity to rest on the plaster (especially if your container, like mine, has walls that slant outwards). Make chambers slightly thicker at the top side than the bottom side to account for this. Be careful to leave enough space between chambers and tunnels that they will be structurally sound.
Once you’re happy with your nest arrangement, mix up some plaster and pour it. Contrary to the chambers, you’re going to want the plaster of the nest to be thicker at the bottom of the container than the top, so prop up the top edge slightly while you do this. Make sure the nest is thick and sturdy.
If you want to add some texture to the back face of your plaster nest, now’s the time before it hardens to much. You could sprinkle sand, small pebbles (let the plaster dry a bit more), or get creative with whatever comes to mind. I found white, glow-in-the-dark sand for hermit crabs at PetCo and had a lot of fun with that.
Let the plaster set according to the directions. Then slide that sucker out of there and carefully remove the clay and saran wrap. (This is easiest if the clay is still wet.) A beautiful cast ant nest! If you’re feeling especially creative, this is also your chance to paint some color onto the flat wall where it will sit against the container. (Don’t paint in the ant’s living space!) Make sure the whole thing’s completely dry, then it’s time to stick that thing back into place.
In getting it into place, you want to make sure the nest is a tight fit, particularly against the front wall. With a good cast, this should work out fine on it’s own, but you may want to think about some sealant. I used some glue along the sides as I put it into place, and then ran a line along the edges and top where it met the wall to seal up the cracks. Because I had some, I used “Amazing E-6000” but epoxy or a hot glue gun would probably do the trick. (You can even sprinkle some sand on the wet glue to hide it.)
If all you want is an ant container, you’re done, but now’s the time to work on their foraging area. I wanted to cast a plaster bottom to help everything stay in place, and to secure some sand substrate.
You won’t need a mold for this part, but before pouring any plaster, make sure you use some clay or other material to plug the nest entrances so that they won’t get submerged. Be careful, you need to be able to get the clay out again! Then it’s as simple as pouring in a base of plaster, however thick you like. (I chose thin, to keep the weight down.) If you have any landscaping you want to secure, sink it in the plaster now. Silk and plastic plants for fish tanks, rocks, branches, plastic flowers are all fun. Or abandon the naturalistic setting and give your ants legos and barbie dolls to forage around. Follow your bliss. Plan ahead for cleaning and feeding. Crowded tanks can be a pain to work with. Also make sure decorations don’t stick up too high and give the ants escape opportunities. As always, remember a 2-3″ lip.
Now, quick, before it dries! Add your sand/substrate/texture. You can also include loose substrate, later, but remember, if it’s deep enough, the ants will move in there instead of the nest. Ants love dirt.
Once again, let it dry. When the plaster’s sturdy enough, remove the clay from the nest entrances, and use your glue again to seal any gaps and crevices (followed by a sprinkle of sand!).
You’re almost done! Now let’s work on making the container as escape proof as possible. For most ants, this means a band of vaseline. The thicker the band, the less likely you’ll have strays. You can use the lid to maximize out-of-sight vaseline (plus upside down vaseline is particularly hard to walk on). If you’re using a vented plastic terrarium lid, you’ll need to create a smooth, solid surface to apply the vaseline to. Use scotch tape or packing tape to carefully cover up the holes in a ring around the underside of the lid. (You don’t have to cover all the holes, you just need to make a broad ring from the outside edge. Some ventilation is still good (especially in a humid climate!). I generally take the plastic door off, or leave it open.) If you’re feeling particularly motivated, you can even make this a permanent solution. Once the tape is applied, go in with you hot glue gun or some putty on the top of the lid and fill in all the holes.
Done? Apply a liberal coating of vaseline under the lid and around the top rim of the container (the ring on the container has the added advantage that you will be able to take the lid off if you need to, for example, fix up the vaseline without a massive ant escape.
And that’s it! You’re done!
You will need to supply your ants with food (sugars and proteins) and water, as well as keep the nest damp* by squirting some water down onto it to absorb into the plaster. (Variable moisture conditions in different parts of the nest will allow the colonies to naturally regulate the moisture levels of their brood.) For protein try crickets or tuna fish, and consider using a dish to help keep the substrate clean. For sugar try watered down honey, or sugar water in a tube capped with a cotton ball. A water tube can be provided in the same way. Ants like any number of foods so try things and see what’s popular.
*Wait, back up! If you’re having moisture problems, consider sticking a tube down into the top face of the plaster nest while it’s setting. This tube can help you add more water to the nest rapidly, as it will hold the water for the few minutes it takes to absorb down into the plaster. You could even coat the outside of the tube with vaseline and have it project up through the lid for easy watering. For very dry climates, consider using something to “seal” the back face of the plaster nest as well.
I hope this has been helpful to you! If you do make your own formicarium I’d love to hear your stories and see pictures!
See also: More formicaria designs!
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