Soda bottle desktop mini worm farms

[Jay Blair]

Terril told us on the other board that she used 3 liter soda bottles in teaching students about worms.

This got me to thinking of how to make a bin of two soda bottles fit together as a medicine capsule does.

The prototype I built uses green mountain dew 2 liter bottles. The tinted bottle offers a more hospitable environment for the worms.

I cut the tops out of the two bottles where the top edge of the label is.

I kept one top and made two splits up the sides so I coulld force it over the bottom half of the bottle it was cut from. I then wrapped around it with clear box tape (duct tape would work but is more expensive) to seal the air gaps formed when the split top was expanded to fit over its bottom to form a 1.5 liter "worm capsule".

In the very bottom of the worm capsule I use an exacto blade to drill 2 or 3 drain holes no larger than 1 / 32 to 1/16th of an inch in diameter for drainage.

I then set the worm capsule into the second bottle as a catch tray for any moisture.


Next step is developing suitable bedding material.

any ideas?

[JudyA]

Remember when 2 liter bottles had those cool little back bottoms? They could be popped off, then when the tops were cut down, the top could be inverted over/into the black bottom piece to make a terrarium? Now, I've dated me.

[theinfamousj]

JudyA, I wish they still had them. It would make a fitting (and relatively free) project for my high school biology students. I have, however, come up with a modified version of it.

[tt]

pictures of the bottle workshop i did today. 65 students in 2 hour . Not enough time should have been 3 hour. I had to come home and sleep for two hours. Kids were great but very noisy . Anyway got a few pictures up
www.standinghorse.com/wriggler/bottle1.html

[theinfamousj]

I've been messing around with this concept and came up with what I can find as the best fit. Bear with my instructions (the next time I get a green 2L, I'll photograph the instructions for better explanation).

Take a 2L soda bottle and trim about 1/2 inch below the label. I leave the labels on for this part to help find that spot. Cut all around the bottle. Cut 4 slits into the top of the bottle that are parallel to the sides. This makes it easier to jam the top of the bottle on to the bottom, which is what makes the seal.

Fill the bottom of the bottle, to the top of the little feet, with water.

Add shredded paper and worms to the top of the shredded paper.

Put the top back onto the base of the bottle, jaming it over those slits (which help the base compress. Open the cap 1/2 of the way to allow for air but no buggies.

Leave alone.

First of all, the worms will head down to the moisture in the bottom of the bottle, but that moisture seems to be the right amount to moisten up all of the bedding and keep it that way.

The tea drains down into the "feet" but then gets reabsorbed as necessary. The worms can, but aren't forced to, live down in the feet. So far, no drowned worms (going on 2 months with this setup in my overairconditioned and amazingly dehydrated classroom).

Now I just have to figure out if I can add BSF larvae to the bottle as I described it. Those puppies have no legs or worm-scaling-of-the-sides skills, and so can't avoid death by drowning.

The reason it is such a closed system is that anything more open tends to dry out too quickly in my classroom. This might just be something special about my room, though, since the school had a mold problem and are really, really watching the relative humidity.