A varied diet will keep your fish healthy and hopefully they will live longer.
The majority of saltwater fish keepers feed their fish frozen foods as the main source of diet. This is because frozen foods are extremely nutritious for reef fish and are easier than feeding live foods, unless you’ve bought them. In fact certain fish only eat frozen/live foods and will not touch pellets or flakes.
The benefits of feeding foods that are similar to what is available in the ocean, is that the fish will thrive. They will be brighter in color, healthier with stronger immune systems. This therefore makes them more resistant when it comes to fighting pests and diseases. They will also be more active.
But as long as frozen foods make up the largest part of their diet, it’s not to say that you can’t also supplement feed with other foods such as pellets or flakes. In fact, this is what a lot of saltwater aquarium keepers do.
Getting your fish to eat pellets or flakes is also handy for when you are away on vacation and you won’t need to rely on someone being there every single day to feed your fish.