The Melon-headed whale shark is occasional as it primarily life in intense waters, exactly where number of people go. Plus the bonnethead shrimpfish is rare as it life solely in salt water, exactly where much less people today go. All these are best environments for rare fish to live in. https://aquariumtankrental.politics.blog/2024/10/18/how-to-maintain-a-2-feet-aquarium-bigger-fish-tanks/