Having gone through two years of graduate school with a 150g tank, I would say it's doable if you have few corals or at least, easy corals that don't require heavy maintenance. Going fish only or softies has allowed me to keep costs down. I don't have to do water changes all that often. The only thing I need to keep up with is making RO/DI water for top off every other week. As far as food is concerned, if you're strapped for cash, pellets go a long way, with frozen food feedings every so often. In my two years of being a poor graduate student, I learned to appreciate the fish that I had in my possession, and allow the tank to just run on its own with minimal maintenance. I know times are tough, but an RO/DI will save you a lot of money in the long run. And if you're running some kind of reasonably/budget priced LEDs, you can hopefully reduce some of the electricity costs. Winters are tougher because the heater tends to run a lot more often. If your signature is up to date and that is the size of your tank (without sump and decent skimmer), you may be OK, but perhaps need more frequent water changes. But like I said, if you keep your stocking choices simple and minimal, you should doing alright.
Good luck to you and your partner! I feel for you because when I started school, I went through the same dilema and considered breaking down my tank, but I could not. It was my baby and it got me through tough times in life and school. Hang in there! You will both bounce back!
