Is it IODINE or IODIDE!!!!!??? Because I find it rather odd that someone would put an item like that on the market.??? Maybe you would have to use a 1/4 of a drop that comes out of an extremely small eye dropper. Most of these are kind of toss and serve though. For instance I add an additive that contains all the heavy metals. Which helps hard corals, live rock and soft coral absorb the nutrients in the water more easily. Things containing copper, DUHDUHDUHHHH!!!!!! it is in such a small dose though, that it will not harm inverts. (under .0001 mg). It is a amino acid and metal trace element so all are in extremely small doses.
Similar to way that I am only adding snails to my tank instead of hermit crabs. From what I have read, there is not a hermit crab on the EEEEEEEEntire PLANET!!! That will not pull a snail out of it's shell. So I opted for snails. The Scarlett Reef and Neon stripe blue legs are supposed to be less likely to do it, but it isnt worth the chance. I have 50 nassarius vibex, 20 trochus and am getting about 10-15 cerith snails. All of them are supposed to get along.
Your water chemistry however is more or less like every other chemical compound on earth. I can make a reccomendation - however it is your decision if you try to use it. Most bottles say things like "add 1 capefull for 50 gallons". Start at about a tenth of what it says and continue with that during the same dosing days and after two weeks see if everything is improving. Seeing as how people use MANY different substrates and other things including activated carbon (which reduced trace elements in a tank), it shouldnt be exact like every tank is put together the same. That is what I am doing right now. Now that MY tank is nearly completely cycled, I am adding trace elements and filling it up to the first threaded line instead of putting two whole capfulls in like it recommends. After two weeks if I do not see a hike in coral expansion or coralline growth, I will go up to the second thread.
Also many of it varies based on what you have in your tank. If you have 10 pounds as opposed to 100 pounds of LR, you are obviously going to need a lesser dosage of whatever the bottle may call for.
