5 replies to this topic

[prettycode]

Anyone tried using pieces of PVA sponge instead of cotton balls in their test tubes? (If you've seen the laser-cut acrylic AntsCanada formicariums with blue sponges to control hydration--those are PVA sponges.)

 

I've got a camponotus queen I want to hibernate, but the cotton ball in her test tube is super gross looking. Much more so than the other test tubes I made around the same time.

 

Was hoping swapping cotton for PVA might prevent this.

Edited by prettycode, September 26 2015 - 5:07 PM.

[Crystals]

I would try it with an empty tube first.  It is more porous than cotton balls and could flood more easily.

 

If you use it to plug the entrance, don't be surprised if your Camponotus chews through it.  I made the mistake once of using foam while trying to get more air flow, the queen chewed through with no problem.

[Foogoo]

I've tried it, it's tough to do. Too loose and it dries up in days. Too tight and it doesn't transmit water. I gave up on it after a few experiments, especially since it doesn't offer many (if any) advantage over cotton.

[prettycode]

I've tried it, it's tough to do. Too loose and it dries up in days. Too tight and it doesn't transmit water. I gave up on it after a few experiments, especially since it doesn't offer many (if any) advantage over cotton.

 

This is what I ran into initially.

 

What I've discovered is that I can drill a cork that is the inner diameter of the test tube. For example, I'm using test tubes with a 16 mm inner dimension. If I cut out a cylinder of PVA that is about 16 or 17 mm in diameter, it fits when both completely dry and when completely saturated. 

 

I had to get a number of diamond-coated hole saw drill bits to get precisely-sized cylinders of PVA, though. They're super cheap but annoying to have to get more specialized tools. Also, the sponge has to be completely dry before you drill out your PVA cylinder.

 

After I got the right sized PVA cylinder, I had to try various heights for the cylinder to determine which would allow moist sponge on the dry side. If the cylinder is too tall, no water makes it through to the dry side of the PVA.

 

The advantage I'm hoping for is reduced molding. We'll see--like you said, probably won't make a difference.

Edited by prettycode, September 28 2015 - 10:45 AM.

[drtrmiller]

Good work. Keep up the experiments.

[Foogoo]

This is what I ran into initially.
 
What I've discovered is that I can drill a cork that is the inner diameter of the test tube. For example, I'm using test tubes with a 16 mm inner dimension. If I cut out a cylinder of PVA that is about 16 or 17 mm in diameter, it fits when both completely dry and when completely saturated. 
 
I had to get a number of diamond-coated hole saw drill bits to get precisely-sized cylinders of PVA, though. They're super cheap but annoying to have to get more specialized tools. Also, the sponge has to be completely dry before you drill out your PVA cylinder.
 
After I got the right sized PVA cylinder, I had to try various heights for the cylinder to determine which would allow moist sponge on the dry side. If the cylinder is too tall, no water makes it through to the dry side of the PVA.
 
The advantage I'm hoping for is reduced molding. We'll see--like you said, probably won't make a difference.

Interesting, keep us posted. I initially played with PVA hoping to reduce tugging and tunneling, since there's no loose fibers flying about.