If your feeding in a smaller separate tank then he could live in a little larger enclosing.. That is if he is not stressed from the large area from the start.. Some do well with feeding in separate enclosures, but I have a few that will feed nowhere other then their home cage..
You could use a mega ray if the temps are properly adjusted to make a basking spot of 105-110 surface temp, and a cool side with a ambiant temps around 75-80. May be difficult to accomplish in a 20L. I think you'll have a better chance getting temps correct by sectioning off the 65 gallon tank.
Putting a 20 inside a 65 is accomplishing nothing. It's a 20 no matter what you put it in. It may even cause temps to be higher as it is enclosed in another cage.
Good luck with your new dragon
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I've been entering a pretty large poker tournament the last four years. This yeah I finally placed. I came in 2nd over-all, and the prize was a 2005 Hummer H2 Black with tan leather. I waited 4 weeks (had to pay some tax etc.. all the crap they don't mention when you WIN something LOL) and finally got my Hum V
I drove it for 2 days.. Of course I showed it off to all my family, and friends. I went to the pump to fill her up on day two of driving my way out of my league Hummer H2, and as the numbers zipped around It sunk in that this tank was never ending.. either that or they didn't put it in the tank at all, and were actually flooding rt 37 with unleaded.. Nope it was in the tank.... 31 gallons to be exact... After pulling out my visa, and paying $82 it sunk in that my new hummer would not be ideal LOL. Is this irony or what..
will trade 2005 Hummer H2 black on tan loaded pwr moon roof, leather, onstar for a 2005 Honda Accord/civic Hybrid