My observations are :
Jars 3 and 4 did the best in terms of survival. They both supported life the longest.
The PH and O2 levels only varied slightly and took a lot longer for this change to occur.
The plants started to turn yellow and some even brown after the second week.
This is because the small snails are not giving off enough CO2 in order to support the needs of the plants.
The plants in jars 1 and 2 began to yellow very quickly. There was no source of CO2 for the plants to survive.
The PH level changed from 7 to 6.5 indicating that an imbalance was starting to happen.
The O2 levels as well changed from 5mg to 2mg. This decrease indicates that the plants were not producing O2 because there wasn't any CO2.
These jars developed a very bad odour in the remaining days due to the decaying plants.
The 3 of the 4 snails in jars 5 and 6 died at the end of the 1st week, with one still alive. These two jars had the greatesat change in Ph levels.
The oxygen levels had the biggest change as well, (8mg-11mg).
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