water dragon tank outside? 10 points?

  i have 2 eastern water dragons and at the moment there in aglass tank in my room but i was going to make them a nice big tank in my room but then saw a enclosure outside with a pond and it was really big and good with turtles in the bottom and i think it will be better if it was outisde and my turtle could also live with them. my lizards are only like 35 cms but out side with lot of room they should grow quite quickly also in sydney at this point it is starting to get really warm which is also a bonus. should i make it out side with my turtle and how big should it be?
I just moved to a warm climate and had my dragons outside and they loved it. Their colors got very vibrant and they were very lively. Unfortunately its too cool at night for them now so I had to bring them inside.



I would be a little wary of putting them in with turtles though. Turtles have been known to bite off dragons toes and tails. They look like worms in the water
There is nothing better than natural sunlight for a lizard. You might still want to build that tank for your room unless the Sydney winter's are not that cold. You still have to maintain the minimum temperature requirements for the species. I know many people here in the US that live in Southern Florida keep tropical species outdoors most of the year. If our winters weren't so harsh where I live now, I'd keep my snakes in outdoor setups. Just make sure that predators do not have access to the animals. Edit for further comment: I would not use a glass enclosure (if that's what you implied in your question) as glass is too much of a hothouse in the sun. You'd fry your lizards in no time if the sun hits the glass. Most outdoor enclosures for turtles, snakes and lizards are concrete with screening of some type that will let in the UV light and air. Most are built around tree stumps etc with branches and leaves to hide under to cool off and plenty of ground cover for terrestrial species.