# Predicting good weather



## Elliott225 (Jan 9, 2014)

Being a bit of a weather geek, I've noticed some times the air stone in the Betta's tank bubbles slow down when the barometer is rising. When there are lots of fine bubbles the barometer is falling. It's the weirdest thing I've ever seen.


----------



## emc7 (Jul 23, 2005)

PV=nRT. so Volume is proportional to Temp/Pressure so, all other things being equal, lower pressure should equals bigger bubbles. And lower temp should means smaller bubbles. But I'm sure that isn't the whole equation, the speed of the bubbles through the stone also depends on temp and pressure and that affects the size of the bubbles created and the speed they leave the stone.

If you are actually measuring the change in pressure instead of just a snapshot of current conditions, its very interesting. I'll have to start watching my air stones.

It should by pretty easy to make your own barometer with a u of airline tubing and colored water.


----------



## Elliott225 (Jan 9, 2014)

The bubbles are larger when the barometer is on the rise.


----------

