His work, which was documented and repeatable, contradicted the accepted cell theory, so a change in the theory was required.
The nail breathes oxygen to live. The nail breathes the oxygen dissolved in the water.
Given that the aquarium is a small bioma there is not enoguh source of oxygen to replace the oxygen consumed by the snail, except for the oxygen produced by the aquatinc plants inside the aquarium.
Plants produce oxygen through the process named photosynthesis. Photosynthesis requires light.
Given that the aquarium is kept dark, the aquatic plants cannot carry out the process of photosyntthesis and so there will not be generation new oxygen and the snails will die after they do not have oxygen to breath.
I
Vapor is your answer my friend
I hope this helps
