I recently upgraded from my 55 to a 75 + refugium. Its been a few weeks and I am now seeing that familiar brown algae you get in a new tank. Is this normal? I know how to handle the diatom outbreak and am not too worried about it, but i didn't expect my tank to act like a new tank.
Even though you are just changing to a new tank you can still experience a cycle. I remember when I did a large water change for my 75 gallon and it did a mini cycle. You have to remember your tank has a mind of it's own ^^
Mine fully cycled when I upgraded, even with all of my LR that I transferred. Killed everything in my tank including all worms and pods. Had to wait 5 weeks for my cycle to finish. Hope you have better luck.