I want to get a mega ray or T-rex for my girls as I wouldn't have to worry about changing the reptisun 10 tube we use every 4+ months now. Anyway, the vivs are next to a south facing window so it gets colder in their viv's at night in the winter and in the warm day's it heats up fairly fast. Last week we had highs in the low to mid 80's. With those temps we are using 60 watt house bulbs to heat their tanks and, temp wise it's good. If I get a 100 watt T-rex or Mega Ray, will the temps in the vivs be to hot with that bulb. We do have 40 gallon tanks, one tank is 15.5 inches wide and the other is 18 inches wide. They are both 36 inches long.
I would appreciate any input people have. I don't have the money to purchase one of these if it will get their tanks to hot. If it will help, we do keep our house thermostat at between 78 to 80 degrees, sometimes a little hotter.
If you have open top vivs then you have a lot more "play room" for adjusting the height of the bulb and the temps in the viv. Heat from the MVB can easily escape. I have my megaray inside of my 4x2x2 and I watch my temps closely because those bulbs can get hot and it has nowhere to go inside of my viv. Before I built my 4x2x2, I had the megaray shining into a 20 gallon tank. I was concerned when I first bought it and I was fully prepared to just keep using my reptisun tube, but I used a deep dome and a lamp stand to elevate it and it worked great. My temps were 105-110 on the basking spot and low to mid-80s on the cool side. If you get the MR 100watt bulb, you have several inches of height to manipulate since reptileuv recommends 10-18" from bulb to basking spot. If you did have a lamp stand, you would be able to easily adjust the height of your bulb. You could also adjust your basking spots to a different height.