I found the oppisite. When I had my male pastel in a tank before I got my female it was super hard to keep the temps up and I was misting 3 to 4 times a day. Now that I have them in the rack I am maybe misting once a day if that and my temps in the back are a solid 87 to 90 all the time. I just know that I am going to have to get them in bigger tubs within the next few months and I am working on getting more insulation in the room that they are in to get the heat in the room up a little.