Do I have to spring for the whole high-tech schpeil or will the old-fashioned box filter suffice?
That is dependent on the amount of time and maintenance you intend to devote to your fish. If you want to have a bare tank and do more frequent water changes (2-3 times a week), then a sponge filter is all you need. Additional filtration in that case is helpful. This is also the easiest to maintain in my opinion, but most labor intensive. If you are going to do water changes weekly with only minimal daily maintenance, then you will probably need UG filter, power filter, etc., depending on the tank and number of fish. It’s not as expensive as it sounds, a one time set up fee and then slight maintenance and cleaning of the filters is all that is required.
