Converting two tanks into one... but one is cycling

[jayking232003]

Hi everyone. I have a 37 gallon up and established. Got the 30 gallon that I started about a week ago, cycling with some live rock out of my 37 and a handful of sand. two crabs. Damsel..
I just got a great offer on a 55 gallon aquarium. Would combining the two be hurtful? The tank itself would have to go thru another cycling period right, but maybe wouldn't take as long since all the bacteria is the same? Help me out here if you could. Thanks

 

[hlcroghan]

You could put everything from the 37 in there but you will have to wait until the 30 is done or you might kill what is in your tank. Or you could just make sure the lr you get is fully cured. Some lfs have that. and then you could start that tank and when the 30 is done, you could transfer it.

 

[salt life]

you can go BB and you won't have a cycle just don't stock it right away. I added another 75g and a new sump to my system, did BB DT and I didn't cycle, it was pretty much like doing a big water change, but my other tank has been running for 2+ years so idk if that makes a difference.
but if you like the sand look then forget what I said lol

 

[tank a holic]

put the 37 into the 55
leave the 30 alone and use it as a sump
turn the 37 into a QT