I am curious about suggested (maximally convenient) methods of performing water changes on large aquariums, meaning 150 gallons or larger. I don't own one now, nor will I in the near future, but once I buy a house in the next couple of years, I plan to get a large tank soon after. Before I do that, I'm curious to hear people's experience and suggestions for how to clean and specifically change the water on them.
My largest tank currently is a 90 gallon, and I do water changes using 34 gallon brute trashcans... I'll prepare 25 gallons of new water in one can, then siphon out 25 gallons into another. Once I've removed 25 of the old, I use a 5-gallon bucket to scoop the new water back into the tank. Problems with this approach are: dragging the filled trash cans around is a bit cumbersome, scooping water from the can into the tank is effective but can be a bit messy, and if I had anything larger than a 90 gallon, I'd need more than two trashcans which would make dragging them around even crappier. There's gotta be a better way.
What do you guys do?