Moo-Desto? ROFL! me too...
Personally, I've always believed that the pretty-colored bottles should be left at the LFS. If you can't or don't test for a substance, you should not be adding it. Otherwise, how do you know how much your tank actually needs?
MOST trace elements are replenished by doing regular and frequent water changes, which is healthy for your tank anyway.
Calcium and alkalinity buffers may be the only exception to that, but STILL should only be dosed after you test to see how much your tank needs.
Blindly adding iodine is dangerous. The line between "just right" and toxic levels is very fine, and iodine is also replenished via water changes. It can force crustaceans to molt, (not help them as is often touted) because it's how they get RID of excess iodine in their systems.
I've been in the hobby in one way or another for 30 years, and have NEVER found any reason to dose trace elements.
Save your hard-earned fishy $$$ for a new fish or coral...