I hope you don't have to tear down your big tank.
Do you know how much of the electric bill is generated by your big tank? I know your tank is bigger than mine, but my 180, 75, and a couple of other small tanks do not add so much to the total electric bill for my house. I don't remember now, but I added up all the power consumption on my tanks based on the wattage and the number of hours they run. I was bracing myself about the total cost, but I was rather surprised that the tanks did not cost as much as I thought. FWIW, except for the three MH lamps, I am using energy efficient equipment everywhere possible.
As for the bubble algae, my bubble algae busting team, foxface rabbitfish and power blue tang, has practically wiped out all bubbles out of my display tank. There are a few in my sump and fuge, but practically none in the display.
Even though some foxface have a bad reputation for eating softies, I think it's worth giving it a shot if you are plagued with bubble algae. My foxface cleaned up both red and green bubble algae from my 120 and 180.
Earlier I thought that my current foxface was nibbling on my soft corals, but it turned out that it was aiptasia which were hiding behind the corals and touching them. He did eat my bambam and tubs blues last year, but he has not touched any other zoanthid after that. When my AOG and scolymia started looking terrible, I immediately suspected my foxface, but I was wrong about that. Now I need to go after aiptasia instead

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