Try building one enclosure larger than you were originally planning, then sectioning it off so that neither dragon can get to each to the other, or see the other. As long as they each have a set of lights, and water and places to climb and rest, they should both be able to grow properly. You'll basically have to make the one enclosures into two enclosures.

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"Let's eat, Grandpa!"
"Let's eat Grandpa!"

Punctuation. It saves lives.

There is no guarantee that exchanging one dragon for another will make any difference in the problem and could actually make things worse since you have no way of quarantining the new arrival.
Since you do not have adequate space to have 2 enclosures your best bet would be to find a new home for one of them.

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Merlin,
What's Life Without A Little Magic!

Yeah, I'm definately thinking not to house two together, in fact, I think that's why I may have lost Jack. He was the healthier of the two, but Zhaodi was always ontop of him in the basking light, the UVB light. I think Zhoadi was the little Emperor of his enclosure and didn't want to share his space. I'm finally just getting over that. It's the first animal I've had that didn't live to/past it's life expectancy.

I have two adult females - no fighting but a little head bobbing. They are currently in two separate terrariums but I am building one enclosure (the size of an entertainment unit) and am putting a mesh divider between the two sides. I am going to make this removable - so they can be together but then separated if need be. Everything on both two sides will be the same - lights and all. I got everything that I needed to build this at Home Depot. What would have cost me over $5,000.00 to purchase only cost me under $200.00 to build myself. I plan to build more and work with a rescue to rehome other reptiles.

I too do not think that getting a different water dragon will solve the problem, but if you have to find a home for one of them its understandable because of the amount of space that the terraniums take up. If you could somehow build something, like maybe staking one enclosure ontop of the other or, like the others have suggested, build a single large one and have it separated down the center I think you should do it. Its deffinatly cheaper to build it youself and being in that sort of business you could probably do it on a saturday afternoon . For our wd it would have clost us around $300.00 to buy the enclosure that we needed but we built our own for less than half of that price and we like it more. It doesnt see like much of a difference but thats money put away incase of an emergency vet call if it should ever happen. You could keep both but it might be an afternoon at the drawing board. just try and come up with something that you can fit in your house and that will be fine for both of them. Good luck and I hope everything works out alright for you.

I recently had trouble with my bearded dragons ~ I realize they are not the same. It was a bummer, as we too only had room for 1 large tank. Sounds like the WD's need even more space. Sorry you are going through this, but for the health of the poor guy it sounds like you will have to break them up. I also suggest you check out Craigslist. If you are near a big-city you are likely to come across something reasonably priced, and quickly. Good luck!!

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