[mistergreen]

Has anybody kept track of O2 levels?

https://www.sparkfun.com/products/11194

We've always guessed by the fish's reaction but will concrete O2 numbers help us with certain algae or certain health issues?

 

[heel4you]

Wonder if this can be used on an Apex?

 

[mistergreen]

Wonder if this can be used on an Apex?

I doubt it. The controller would need to know how to interpret the sensor's signal (serial or i2C).

Major aquariums keep track of O2 in their tanks. The sensor is now affordable enough for us to keep track too.

 

[mistergreen]

Here's an interesting article on DO.
Dissolved Oxygen - Environmental Measurement Systems

Over the summer, we had a fish die off here in the local lake because of low DO. I guess it's important for you guys who keep tanks with 80F+ to keep track of DO.