New tank discussion

I am finally getting very close to putting water in my new (to me) 240 gallon glass tank. The stand should be finished today and then tomorrow I will test it with tap water for leaks. Hopefully by Sunday night or Monday I can start filling with Salt Water.
Here are my thoughts on adding this aquarium to my existing 200 gallon reef system. I would like opinions on whether I am off base or not.
When I fill the 240 with water it will be bare bottom and will only have dry rock in it. I plan on bring all controllable parameters in line with my reef system over a period of a few days. pH, Temp and salinity are what I will concentrate on. When these are in line with my system I want to hook the systems together and start mixing the water very slowly so it will turn over the 240 gallons in say a day or two. Since I will not have any life in the 240 I do not see a reason to cycle the tank since my current biological filter can handle my bioload. It should be like doing a very slow 60-70% water change.
Then I will start moving fish and live rock from an existing 55 gallon tank in my system (aggressive tank) to slowly convert this tank to the 240 and tear down the 55. The 240 will be the new home for my Puffer and Lion fish since the lion fish is starting to wear the 55 as a hat. They are both growing fast.
So please punch holes in my theory if I am wrong.

 

Thanks for the replies guys. I completely understand about the dangers of all tanks being on the same system, that is how I have them now. I do worry about it. I figure it is the same as someone having an outrageously beautiful 400 gallon tank that if something goes wrong you will lose it, JJ comes to mind. I have enough trouble getting the time to appropriately care for one system, I wouldn't do this if I had to setup another system. It just wouldn't get taken care of. So far I haven't had a major problem having three tanks (display, aggressive and frag) on one system.
Travis, hopefully with proper QT and good husbandry I will never have ICK again. Knock on wood.
What I was most concerned with was not cycling the tank and just mixing the waters. It sounds like a great plan to me and biologically feasable. I talked to Allen Mabee and he thinks this is a good plan as it was what he did on his last tank. He didn't have any problems.
If anyone else has any reasons I shouldn'ty go this route chime in. Thanks again for the replies.

 

Going well. I have had the tank filling with RO/DI since Monday night. As we know that takes awhile and is only 2/3 full. Hopefully it will be full tomorrow night and I can work on the params. Temp is maintaining currently.
Thanks for asking.