Particularly discus, cardinal tetras, rainbow channa, rams, and other colorful species. Im debating whether to use white sand or black sand and have read and observed that lighter substrates such as white sand create a more open and welcoming aesthetic and dark substrates can create an entirely different aesthetic. i've also read that cardinal tetras colors become more pronounced with a darker substrate and that polypterus can darken with darker substrate. If anyone has any opinions or knowledge on the subject i'd appreciate some input
