there is no backround so i think that might be the plug for the filter hanging down, the tetra filters cant pull the water up if the exstention piece junction w/ the filter tube is above the water so i put some silicone on it and it works great
It's something with a plug that I am seeing. Not a big deal, I was just curious what it was. Especially since I could see the heater. Could be the combination of the themometer and the plug from something else.