I purchased a plant for my 10 gallon fish tank yesterday. This morning, it shed all its leaves and dropped to the bottom.
It was a large floating plant, with needle-like leaves. I don't recall what is was called though. The salesman who sold said said it could also be anchored to the ground for floated, but recommended floating it. It was longer than my fish tank, an I assume it was probably way too bid for a 10 gallon tank. My tank is unheated and unfiltered at the moment. The other occupants of the tank are a male betta and a mystery snail. The betta is doing fine, but he seems to a quite hardy specimen.
Could the plant had died from lack of carbon dioxide, if it was too large? The tank is unheated, but the room generally stays above 68 degrees. I am aware that the temperature is below the recommended range for betta fish, or most tropical tanks, but the fish doesn't seem lethargic, and I don't want to introduce unneeded changes to the system rashly.