Okay so that last thing I built for my Acromyrmex seems to have killed half the workers in the colony I put in it. I have no idea what it could possibly be, as it was nothing but plastic boxes, vinyl tubing, stainless steel mesh, and a sponge. I do use a solvent to bond the plastic pieces together, just like anyone who builds acrylic cases for pets. This solvent while still wet is quite toxic, but once it has evaporated and cured, it's no longer there and no longer dangerous. All I can figure is it didn't cure long enough, but that's weird because it evaporates extremely fast, and the thing sat for almost an entire day before I put the ants in it. Either way, I probably won't ever find out what the problem was, because I have since come up with a much better formicarium for these guys.
 
Here's the new leaf-cutter formicarium.
 

 

 

 
 
I based these on the same design used by Dr. Rebecca Clark from Texas A&M University. These here are the ones she made.
 

 
 
As I always do, I added a hydration system to mine for convenience and consistency. I sealed up one of the shorter medium sized containers to make a water tank. I then created a port where a long narrow sponge sits and acts as a wick for the water. The sponge is small so that it can be easily pushed down by the weight of the container sitting on top of it, ensuring good transferring of the water from it to the Hydrostone in the floor of the chamber container.
 

 
 
Here's the bottom of the chamber container. You can see the Hydrostone port that comes through the bottom. This is part of the Hydrostone floor of the container, so it becomes damp when the sponge touches it. The Hydrostone around it, separated by the plastic ring, is there just  for weight, and purposely segregated from the port.
 

 
 
Here are both the chamber container and the foraging container. I added Hydrostone to the bottom of the foraging container for added weight as well.
 

 
 
I should be testing this out over the next few days, so as always, I'll report back here with the results.

Last night I put some extra Camponotus workers in the nest  to make sure it isn't going to mysteriously kill anymore of my Acromyrmex.

 

I put a hygrometer in each chamber to measure the humidity difference. At first both containers were 94% humidity, but later today, I found the foraging container at 87% and the fungus chamber container at 92%. I checked the humidity in one of the foraging containers I currently have the Acromyrmex in, and it's only about 70%. This is most likely going to result in mold growing on the substrate.

I cut out the majority of the lid on the foraging container, leaving just a small lip that I can glue some steel mesh to later.
 

 
 
I tested the humidity again after about 30 minutes, and it was down to 78% while the fungus chamber hadn't changed at all, still reading 92%. This is perfect! As I predicted, the water is wicked up into the fungus chamber fast enough to keep the humidity up even as its constantly escaping through the foraging container.

Late last night, I attached some stainless steel mesh to the foraging container lid, and moved a medium-sized colony into it.
 

 

 

They like all that open room at the top?

Apparently. Did you see Rebecca Clark's setups? She started the colonies in those things.

This is a very interesting setup.  I am very curious to see how it grows.

I think this will work very well for the fungus growers.

Yeah, based on what's been used in laboratories, this should work well. Dr. Rebecca Clark even said as long as it stays humid enough, she thinks it should work "fantastically".

So far these Acromyrmex formicariums are working great. I have two colonies moved into them right now, and should be moving another five in tonight.
 
Last night I made a jig for drilling the holes in the containers.
 

 
 
I have planned to do this for all my formicariums once I get the design finalized. Since this fungus-grower formicarium was pretty basic, I figured the design is final for the most part and I decided to make a jig for it now. Measuring and drilling the holes in the containers for one of these formicariums took about an hour before, and now with this, it takes exactly five minutes. Even though it took a few hours to make, this jig and others like it, will save me tons of time in the long run.

I made these stackable.
 

Man if that was in my house someone would knock it down and there'd be a mess...

  That's why I don't have kids in my place, or anyone for that matter unless they're guests.

Problem!
 
The capillary action erosion problem strikes again. This is a strange phenomenon that causes problems for me all the time. I haven't been able to find any information on this anywhere on the internet, let alone find a word for what is happening here. Basically anywhere any material transfers water via capillary action to another material like Hydrostone or Ytong, there seems to be some sort of erosion that takes place. Whether it's a string, sponge, or anything else, it will eventually eat its way into the material over time. This seems to only happen to cement type materials like gypsum cement (Hydrostone) or Ytong, although I haven't really tested any other materials other than plastics likes sponges which don't seem to have this problem that I can see. The higher the rate of water flow, the faster this happens. I noticed this when I was testing an idea I have for a hydrated cricket bin by putting peat moss in one of the fungus chambers of these. After about eight hours, and after a relatively large amount of water had passed through, WAY more water than would pass through one of these while being used for ants, it had formed a small pinhole all the way through the 1/4 inches of Hydrostone.
 
Here's what the Hydrostone port looked like.
 
Top
 

 
 
Bottom
 

 
 
Here's the bottom side under a microscope.
 

 

 
 
Unless I can figure out how to stop this from happening, It looks like the only materials that are going to work with a hydration system will be plastics.

I agree with whoever said in chat that it may be the Ph of the water.

That could be part of it, or all of it... I wish I knew. This might just take some experimenting.

Whatever it is, it is a really cool phenomenon. Have you ever thought of making your own mini scale hydrostone stalactite caverns?

Strangely enough, I've never thought of that.

I wonder if hydro stone mineralizes like limestone does, and be able to make stalagmites and stalactites...

I wonder if hydro stone mineralizes like limestone does, and be able to make stalagmites and stalactites...

 

Given that these generally take tens or hundreds of years to form, I'm not sure it would be an idea worth exploring.

 

It may be possible to accelerate the formation by using a thin string as a drip line, then finding the optimal ratio of salts and minerals to use as a drip solution, as well as the optimal rate of flow.  

 

But in the end, you have to ask yourself—why am I doing this?  What problem am I trying to solve?