i have a reptile tank for Green iguana and I dunno whether it's big enough or not?

Not even close. Iguanas need a huge amount of space! An adult iguana will need an enclosure as big as a decent-sized bedroom.

No, not at all.

Tail included, your lizard needs to be able to move freely, even with the basking areas, cover and climbing things he *needs*.
If he bolts (which small iggies are very, very likely to do), he is going to slam right into a wall very quickly and do himself damage.
Honestly, I wouldnt house your guy in anything less than a 3x3x2ft for now.
They are active lizards that need a lot of space.

Ball Python palms down. I worked for a at a similar time as at an Iguana rescue place, and specific, you may get somewhat greater interaction with an Iguana, yet no longer all that interaction is going to be friendly. they could be very aggressive for no obvious reason, and are available breeding season they're aggressive each and all the time. That, paired with their extensive length, makes for a rather risky first reptile. i could commence with the python, commencing with the decrease maintenance animal is possibly terrific while determining if reptiles are extremely your concern. If some years down the line after looking after another reptiles and additionally you have accomplished a lot of study and nonetheless choose an Iguana, choose for it. yet i could wait till finally then, because of the fact they're a ton of artwork, each and every day. There are different super lizards that are a lot greater handy to maintain and have nicer tendencies, i could study a number of the smaller video show instruments (smaller than a Savannah) and tegus if I have been you.

A baby can live in a 20 gallon but an adult will need a custom built terrarium or tank that's 12ft long, 6ft wide and 6ft high