A few words on crowding and its relevance. In the book we cover the proper amount of fish to keep in what-size aquarium with “per inch-per-gallon” guidelines but there are variations.
For example, if your system has constant water replacement, you can have a LOT more fish. If the system has no filtration and relies on mollusks and live plants, then fewer fish is the order of the day. But, can illness be caused by UNDERCROWDING? When is “crowding” actually important?
VIDEO: Crowding. How Could THAT Be The Whole Problem?