I maintain a 40 BR in my essentially unheated laundry room for my Orange Spot Sunfish and space considerations over the summer caused me to add a couple of Panda Garras, Garra flavatra. I've been keeping an eye on water temps each morning and observed a few days ago that at 59 F the Garras show normal activity levels and response to food. Each day since the temp has dropped a bit further with decreasing activity levels. Finally today at 52 F they're inactive and show no response to food. I expect water temps to drop even a bit further as the winter progresses so I guess they have to go into the living room tank.