Guppies, algae eaters, and albino corys can tolerate some salt in their water, which can be beneficial for reducing stress and promoting healthy gill function. However, it's essential to use aquarium salt rather than table salt (NaCl), as table salt can contain chlorine and lacks the necessary minerals for proper aquatic conditions. Each fish species has varying tolerances to salt, so it's crucial to research appropriate salt concentrations for each type. Overuse of salt can be harmful, so moderation is key.