I used to think small was hard, but I've been following posts from one of our users that changed my mind. Check these threads and the threads that get referenced. I'm under the impression that it's just so simple to keep clean and to do nearly 100% water changes that it's a really viable option, especially on a budget.
https://www.reef2reef.com/threads/w...a-fishbowl-than-in-a-normal-reef-tank.270506/
An option I'm considering is taking a 40 breeder (inexpensive and widely available) and having a piece of glass cut to make an AIO out of it by portioning off maybe 6" of one end for equipment. I'd just keep that end to the back and view it from the other end. A small pump would be a fine return and a heater would easily fit. I'm not sure about nutrient control, but I'd think that an algae scrubber would be a good fit.
https://www.reef2reef.com/threads/w...a-fishbowl-than-in-a-normal-reef-tank.270506/
An option I'm considering is taking a 40 breeder (inexpensive and widely available) and having a piece of glass cut to make an AIO out of it by portioning off maybe 6" of one end for equipment. I'd just keep that end to the back and view it from the other end. A small pump would be a fine return and a heater would easily fit. I'm not sure about nutrient control, but I'd think that an algae scrubber would be a good fit.