Balance is the key. At the core, understanding the nitrogen cycle will inform any aquarium keeping. From my experience, a more hands-off approach -- benign neglect -- works best for anything other that hardcore biotrope aquaria, high-tech planted tanks, or breeding demanding species. In any case, better to first work on keeping a balanced tank, which means getting a handle on water quality, light, and nutrients. Reduce variables; don't add more (i.e. carbon additive). Shield the tank from direct or strong sunlight. Don't overstock or overfeed. Work with your lighting levels (time and intensity). Ensure adequate filtration and water changes. Once you have things balanced and have whipped the green water, then branch out into wherever the hobby leads you: more plans, more tech, more demanding fish, etc.