Drain the 180 g tank down to 1/4 full. take the brace out. put the 55g tank in. put the braces back on. And refill.
... I was mainly just asking for ways in which I could do this without removing the tank or emptying...
Drain the 180 g tank down to 1/4 full. take the brace out. put the 55g tank in. put the braces back on. And refill.
Can you remove the 180 from the stand and drop the 55 in from the top, correction don't drop place.