Ever wanted an ant farm? Ant farms are entertaining, yet educational – it’s fascinating to observe the little ants as they go about their busy lives. But store-bought ant farms are often expensive, and usually limited in size. If you’d like an inexpensive, easy-to-make ant farm alternative that gives ants tons of space to lead a more natural life, then this soda bottle ant farm project is for you!

Step 1: Materials You'll Need

One of the great things about this project is that it mostly requires materials and tools that are inexpensive, common household items. You’ll need the items pictured above, as well as a few other things -- here's everything you'll need to gather:

• Two 2-liter plastic bottles
• One smaller plastic bottle, between 591 mL to 700 mL in size. Get one that has five bumps on the bottom (like the 2-liter bottles, as shown in the close-up picture above).
• One “Tornado Tube.” These are used to hook two plastic bottles together and are often found in toy stores. They can also be purchased online, such as from Amazon.com: http://www.amazon.com/dp/B000GYSZOI/
• Optional: Hair dryer and Goo Gone to clean the bottles up.
• Utility knife
• Scissors
• Epoxy that works with plastics. I used quick-set, multi-purpose Loctite epoxy and it worked great.
• Soil
• Funnel or construction paper
• Optional: Grass/grass seeds, small leaves, rocks, twigs, etc., to make a natural foraging area for the ants.
• Shipping tape
• Cotton ball
• Ants!

Step 2: Clean Up the Bottles

Empty the three plastic bottles, rinse them out with plain water, and remove the labels.

Tip: To more cleanly remove the labels, use a hair dryer for a few seconds on the parts that are attached to the bottles with glue – this will melt the glue. If there is a little glue residue left, use a product like Goo Gone to remove it.

Step 3: Cut Up the 2-Liter Bottles

Carefully use a utility knife and scissors to cut the bottoms off of the two 2-liter plastic bottles. Cut along the small ridge that’s about 6 centimeters (cm) up from the bottom of the bottles.

You can use the utility knife to make an initial cut, and then use scissors to do the rest of the cutting.

Tip: On one of the bottles, you may want to make a small, triangular notch so it’s easier to figure out how to put the bottle back together later.

Step 4: Secure the Small Bottle Inside of a 2-Liter Bottle

Use the epoxy to attach the small bottle to the cut-off bottom of one of the 2-liter bottles.

Since the small bottle has five bumps on its bottom, it should nicely fit in place inside the bumps of the large, 2-liter bottle bottom.

Step 5: Seal the 2-Liter Bottle Around the Small Bottle

Place the top of the 2-Liter bottle around the small bottle. The 2-Liter top should rest on its cut-off bottom.

Tip: If you made a triangular notch on the 2-Liter bottle, line up the notches.

Use the epoxy to seal the 2-Liter bottle back together. You do not want any big holes that the ants could escape through, so it may take about four or five rounds of applying epoxy and letting it set before you’ve sealed all the cracks. Try not to add too much epoxy in one area at once or you’ll end up with solidified globs.

Tip: Gently blow through the top of the bottle to see if there are any cracks left that need to be sealed up. Listen for air escaping, and use your hand to feel where the air flow is coming from.

Step 6: Add the Soil

Add soil to the top of the 2-L bottle that has the small bottle inside of it. (If you want, you can include some small twigs, bark, leaves, grass, rocks, etc. in the soil.) You’ll want to use a funnel to do this (or make a funnel out of construction paper). As you add the soil, gently tap and shake the bottle so that the soil becomes more compacted.

Tip: Make sure there is soil all the way up to the top of the bottle so that the ants don’t encounter a “drop off” when they dig their way down there.

Step 7: Make a Foraging Area on Top

Screw the “Tornado Tube” on top of the soil-filled 2-Liter bottle, and then attach the other 2-Liter bottle on the top of that (upside down).

Fill the top 2-Liter bottle with some soil (just up to where the bottle widens to its largest diameter). Then, if you want, you can add some grass/grass seeds, small leaves, rocks, twigs, etc., to make a natural foraging area for the ants. You should also add a little water since ants prefer semi-moist soil.

Step 8: Finishing Touches

Put the bottom of the 2-Liter bottle on the top. Flip it so its bottom is facing downward, and push it into the 2-Liter bottle so it fits snugly in place.

This should seal the top of the ant farm pretty well, but if you’re concerned about ants escaping, do the following: Use the utility knife to make small hole in the top (such as in one of the five bumps), push a cotton ball into the hole (so the ants get filtered, fresh air), and then seal the bottom onto the bottle using shipping tape.

Step 9: Add the Ants!

Go find (or purchase) some ants and add them to your new ant farm! When they dig into the lower bottle, you should be able to see their tunnels (since there’s a narrow, soil-filled space between the small and big bottle).

Step 10: Possible Additions/Variations

Make a Mega-Ant Farm!
Make multiple ant farms like this one and connect them together using small, clear plastic tubing. It’d probably be best to connect them in the upper bottle, right at the top of the soil level.

Make it Glow!
You could try drilling a hole in the bottom of the ant farm, through both the smaller and larger bottles, and inserting an LED into the inside, smaller bottle. By doing this you could make the ant farm glow from the inside! (You’ll want to be sure to seal area around the hole with epoxy so that soil/ants don’t escape there.)