a couple of things. my iguanas as they get older will be kept separate. right now i have 3 different enclosures for the 5 iguanas. based on what you told me, i think you need to get your basking spot just a bit hotter. also, your terrarium seems small. is the height the 80cm. you should post a pic of it which would help alot. also, I use a megaray bulb which produces not only heat but UVB which they need to digest their food. There are other brands of lights. do you have a UVB bulb on this enclosure or just the heat lamp