Originally Posted by mattt
I would say the room temp is fine at 76F. As long as the water temp doesn't dip below 70F you should be fine. Plants especially prefer cooler water and I can't see any advantages of raising your water temp any higher. I don't use heaters in any of my 4 indoor tanks and my fish are fine.
Different plants have different temperature requirements and most plants sold for use in tropical tanks require tropical temperatures. 76 degrees is pushing the low end of normal tropical temperatures, and 70 degrees will definitely compromise the immune systems of your tropical fish and may be detrimental to your plants.