Green iguana upgrade enclosure advice

Reptile welfare is almost entirely determined by getting the environment right — temperature gradient, UV lighting, humidity, and substrate all need to match the specific species' natural habitat, and getting this wrong causes chronic stress and illness. Green iguanas outgrow starter enclosures fast, and a cramped setup is one of the most common reasons sub-adults develop metabolic bone disease and behavioural problems. Tell me: how old is your iguana, what size is the current enclosure, and is this a full upgrade or are you also looking to improve the lighting and heating setup at the same time?

Good — 18 months is exactly the point where you need to act fast. An 18-month green iguana is typically 60–90cm and still growing quickly; they need a minimum of 6ft long by 2ft deep by 6ft tall as a sub-adult, and honestly you should be planning for adult size now, which means 8ft tall and 4ft deep eventually. Before I give you a specific enclosure recommendation, two quick questions: are you building custom or buying ready-made, and do you have ceiling height to work with? Some people in this situation go custom MDF because ready-made options at true adult iguana size are limited and expensive.

In that case, the enclosure I'd point you to is the Vivexotic Repti-Home Large Vivarium — the 6ft model. It's 183cm x 61cm x 61cm, so it gives him room to move and climb now, and you can stack a second unit on top later to create real vertical height as he hits full adult size. That stacking feature is actually what makes it the smart buy at this stage rather than something you'll have to fully replace. It's timber construction which holds heat and humidity far better than glass tanks, has good ventilation without drying out too fast, and it's genuinely designed for large tropical species. Pair it with an Arcadia T5 HO 12% UVB tube running the full length — iguanas need strong UVB, and this is non-negotiable for calcium metabolism. For heat, a basking spot of 40–42°C with an ambient cool end of 26–28°C is your target. What's your current UVB and heating setup?

That's two problems worth fixing straight away. A T8 at 18 months isn't delivering enough UVB intensity, especially in a deeper enclosure — T5 HO puts out significantly more and penetrates further, which matters when your iguana is basking at distance. And 32°C at the basking spot is too low; iguanas need 40–42°C there to properly thermoregulate and digest food. You'll want a halogen or ceramic basking bulb on a dimmer stat to hit that reliably, and a digital thermometer with a probe actually placed at basking level, not just ambient room temperature. Arcadia Jungle Dawn LED bars are also worth adding for visible light and plant growth if you're going bioactive. The core recommendation stands: Vivexotic Repti-Home Large as your enclosure base, Arcadia T5 HO 12% UVB for lighting, and upgrade the basking setup to a 100W+ halogen on a dimmer. That combination will transform his environment.

Yes — ditch any sand or bark chippings if you're using those. For a sub-adult iguana the best substrate is topsoil mixed with play sand at roughly 60/40, deep enough to hold some moisture and maintain humidity around 70–80%. It also allows him to dig slightly, which is natural behaviour. If you go bioactive with live plants and a drainage layer, that's even better long-term because it self-regulates humidity more easily. Avoid reptile carpet — it harbours bacteria and can catch claws. Get the enclosure right first, then dial in humidity with a cool mist humidifier on a timer once it's up and running.