I have a divided 5 gallon tank, and my Tetra 2-15 heater isn't heating the water well enough. Before I divided the tank, it kept the water at a constant 76 degrees. Now, it struggles to keep the water above 72 and constantly stays around 74.
Can two heaters be used? Should I invest in a better heater?
Any help is appreciated. My tank is divided using plastic mesh, so I really do not know why the water isn't circulating well. It fills up evenly with no blockages.
You can see in this picture that the heater is located in the center of the tank, and my thermometer is on the far left (not visible.).