Well, here is a prime example of what not so good husbandry can do... I have a display tank, frag tank, refugium, and sump, all plumbed together. Each had its own heater. I say HAD because I found out 5 days ago that 3 were no longer working I discovered this after looking at my tank parameters on aquanotes, from my aquacontroller. Last Sunday night, the 8th, is when I added a new heater (controlled by the aquacontroller this time). Look at the difference in temperature stability since... makes me sick knowing what conditions I put my tank through Some days had an over 4 degree temp swing...