I have 2 Mercury bulbs for my 20 gallon tank. The 100w bulb is about 105 degrees directly under it and the rest of the side of the tank is 90 degrees. The 125w bulb is about 120 degrees directly under it but keeps that side around 100 degrees. Which bulb should I use? I did not take the temp of the opposite side of the tank for either bulbs.
Hi. Thats way to much for a 20 gallon. Infact those bulbs are so strong you should only use them on bigger tanks. How are you taking the temps? You might want to do a basking light and a reptisun tube for the lighting set up until you get a bigger tank. What is the brand of the mvbs?
How are you taking the temps? Are you using a gun or a probe? A 20 gallon tank is just a starter tank for a bearded dragon so I'm assuming you are planning on upgrading at some point. The MVB need to be a minimum of 12" away to prevent any ocular damage in the reptiles. I have a MVB in my 90 gallon tank at 14" from the top of my beardies head when he basks and it reaches around 110 degrees with a 100 watt. I would take the temps with both of them and see what works best.