AvalancheDave
A few months ago, @minnowette (now apparently one of The Disappeared) said that one of the issues he(?) had with the plop or drop method was that he doubted CO2 diffused out of water rapidly when the shipping bag opened.
This and the assumption that ammonia instantly harms fish are the two weakest assumptions made by advocates of plop or drop.
I thought I'd have to perform my own experiments one day but I still searched for any scientific papers that might shed some light on the subject. It wasn't one that was easy to research.
Last night, I found a paper where they did this:


You can see that CO2 doesn't dissipate rapidly nor does pH rapidly increase. In fact, it's quite slow.
I previously mentioned that when I supersaturated a tank to 300% oxygen that it took 24 hours to get back down to 200%.
Another study measured CO2 build up in a tanker truck of fish. The tank was open to the atmosphere and the water was agitated by the motion of the truck and a water sprayer. CO2 still accumulated.
Some fish farms use degassing towers to remove CO2. If CO2 in water reaches equilibrium instantly with atmospheric CO2 levels this wouldn't be necessary.
Ocean CO2 levels apparently lags several years behind atmospheric CO2.
I still want to do my own experiments one day but this one's looking busted.
Special thanks to @minnowette for pointing me in the right direction.
This and the assumption that ammonia instantly harms fish are the two weakest assumptions made by advocates of plop or drop.
I thought I'd have to perform my own experiments one day but I still searched for any scientific papers that might shed some light on the subject. It wasn't one that was easy to research.
Last night, I found a paper where they did this:


You can see that CO2 doesn't dissipate rapidly nor does pH rapidly increase. In fact, it's quite slow.
I previously mentioned that when I supersaturated a tank to 300% oxygen that it took 24 hours to get back down to 200%.
Another study measured CO2 build up in a tanker truck of fish. The tank was open to the atmosphere and the water was agitated by the motion of the truck and a water sprayer. CO2 still accumulated.
Some fish farms use degassing towers to remove CO2. If CO2 in water reaches equilibrium instantly with atmospheric CO2 levels this wouldn't be necessary.
Ocean CO2 levels apparently lags several years behind atmospheric CO2.
I still want to do my own experiments one day but this one's looking busted.
Special thanks to @minnowette for pointing me in the right direction.