I kept fish through middle school and highschool in the late 70s and early eighties. We've had a 20gallon in our house for about 20 years. Most of that time I had a "less is more" attitude towards tank maintenance. A few years ago we started losing fish and new fish seemed to rarely survive a month. We started over with new gravel etc and things were improving until we bought a green ram cichlid that ended up being ill and all our fish died again. We started over in September 2022 and now have a thriving tank of guppies and neocardina shrimp that are breeding prolifically.