i checked the coolside of my viv with a TEMPGUN the bottom of the aquarium and it always marked around 69-72F or sometimes a bit more. So as the Faq says and someone told me in an earlier thread i was worried that it wasn't enough and is suspectable to ilness. So should i just leave it as is or should i add a heatmat on the cool side to? if i should add a UTH is like the picture i posted earlier enough/good? thanks.