Hello everyone! I've currently had my 20G long tank for about 10 months and things have been great! I've really gotten everything under control and managing my tank isn't a hassle at all. I definitely want to upgrade my tank to at least a 55 gallon but don't want to get too out of control with it because I'll be moving within two years. At that point, I'm setting up my dream tank. A few questions for you: Is there a big difference between the necessary items I'll need for a 55 versus a 75 or a 90 gallon? I'd like to reuse as many pieces as possible for an upgrade, but just wasn't sure. Is a refugium absolutely necessary? I'd definitely like to have a protein skimmer and over filtrate. With frequent water changes at least every other week at the absolute worst, is that fine? What are some of the best fish for a 55 gallon? Is there a big difference between the fish I could use in a 55 versus a 75 gallon? I'm only interested in fish only with live rock at the moment. I'll tackle corals later on. Any help would be great! Thanks!