In other news, I removed the drop checker from my tank and stuck it on my mirror in my bathroom. Within a day the color went back to blue.
I had also taken a glass full of water from the aquarium and left it out over night to degass.
I submersed the drop checker (now blue) into the glass of water, and it is staying blue, confirming that indeed the CO2 level in the glass of water went way down.
So I guess I still have no idea why on Earth the drop checker's color stays green even after a night of surface aeration and no CO2.
Weird. But, I am comfortable in believing that green means good CO2 IF it is true that ONLY CO2 can enter the drop checker's water.
I still wonder why other acids in the tank water can't also enter a gas phase and enter the drop checker's water.
Hoppy, can you confirm for me the intent of the drop checker?
In a tank with a giant piece of drift wood, e.g. tons of tannic acid, your drop checker (not the membrane idea) should still give an accurate reading of CO2. Is that correct?
So there is the unstated assumption here that acids other than CO2 cannot pass through the gas pocket inside the drop checker.
I still want to know how we know that... |