I moved that 75 into a 150 in about 3 or 4 hours. I had a DSB, so I moved all the rock/corals into rubbermaids, then drained the water into these and a spare 75g (the sump) thenmoved the sand with a plastic scooper thingy. Then I put the rock back in, arranged it a bit, half filled the tank, then started adding corals. Once everything was back in, I added back the rest of the water, then added enough new water to top up the tank. Having somewhere to hold all the water is key (and lots of towels). I think I tested the new tank for leaks with tap water, easy to fill and then drained it into my front yard. Once you have the new tank filled with the right temp water, move the equipment over. Shouldn't be a big deal. First get the sump/return running, then the heater, then flow, then lighting. Easy!
