Balanced Aquaria

I recently received a grant of five Intel Galileo development boards. These are like arduinos, but beefier, with ethernet and micro SD-card readers. I've been planning to use them with my writing class to have the students perhaps write a little code but, mainly, generate some data that they can use to write about. And I think I've come up with a great idea: balanced aquaria.

When I was a kid, my dad had students create balanced aquaria in his ecology class. They would put some pond scum in gallon pickle jars, seal them up, and then watch. I remember one sat on his window ledge for at least 20 years, quietly photosynthesizing.

More recently, you can buy eco-spheres available in the mass market: even Target has them.

I think I'll have my Writing in Biology students investigate the dynamics of balanced aquaria. I got a little grant to pay for some sensors to let students collect data about what's going on inside.

I've been thinking about this for a long time. What you probably really want to know is dissolved oxygen. But it's hard (read expensive) to measure dissolved oxygen. I spent a lot of time looking for some way to do it for cheap. I found this fascinating bioboard project that offered some tantalizing ideas, but nothing concrete.

Then I discovered that sensors to measure atmospheric CO2 are much less expensive. I believe that measuring the CO2 in the air in the balanced aquarium will give me a satisfactory estimate of the available oxygen, since the two should be in equilibrium with each other.

I'm planning to hook up CO2 sensors and pH sensors. I also got some LCD shields so we can see the data in real time.

Once I get the stuff, I'll do some pilot testing to see what kind of data we can get and what kind of infrastructure I can put in place (with MQTT maybe) to collect and display the data. It should be a lot of fun.