automatic frozen food dosing

I know a lot of people who have LPS and SPS in their tank and dose on a regular basis or have a automatic doser set up. I have tank a mixed reef tank and dose with trace elements on a weekly basis, and use reef crystals salt mix for water changes which is every 2 weeks. It's nothing super fancy...

The Finicky Fish: My intention is to introduce at the same time: a male blue mandarin; a female spotted mandarin; a female red ruby dragonet to my LPS/softie-only bare bottom 50G. It only has 2 ocellaris and 1 helfrichi firefish - I won't add any aggressive eaters that could stop the mandarins...