Activated Carbon and Iodine
- Thread starter pfish
- Start date
Actually, I doubt much iodide or iodate binds to activated carbon in a marine aquarium. 
I personally don't think that iodine is useful as a supplement (many of us dosed it for years, but when stopping, saw no change), but if I were dosing it, I wouldn't stop using GAC.
I personally don't think that iodine is useful as a supplement (many of us dosed it for years, but when stopping, saw no change), but if I were dosing it, I wouldn't stop using GAC.
This. Activated carbon binds iodine (I<sub>2</sub>) well, but not the ionic forms.
I2 is somewhat soluble in water, and it also forms complexes with other molecules easily, including iodide.
It is even more sluble in organic solvents, hence its tendency to bind to GAC.
Additionally, iodide looks a lot like chloride, and since seawater has more than a half million times as much chloride as iodide, the chloride would easily displace iodide from any simple ionic binding site.
It is even more sluble in organic solvents, hence its tendency to bind to GAC.
Additionally, iodide looks a lot like chloride, and since seawater has more than a half million times as much chloride as iodide, the chloride would easily displace iodide from any simple ionic binding site.
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Activated Carbon and Iodine
I don't think iodide will bind to many organic molecules in seawater, so I do not believe that GAC is a major sink for either iodide or iodate. Unless you are dosing Lugols, I2 won't be present in appreciable amounts (and even then I doubt it stays as I2 for long). But, GAC can bind I2 if it is present. I actually do not know whether the reaction product of I2 and I- in Lugols (I3-) can bind GAC or not
I don't think iodide will bind to many organic molecules in seawater, so I do not believe that GAC is a major sink for either iodide or iodate. Unless you are dosing Lugols, I2 won't be present in appreciable amounts (and even then I doubt it stays as I2 for long). But, GAC can bind I2 if it is present. I actually do not know whether the reaction product of I2 and I- in Lugols (I3-) can bind GAC or not
Thanks for the replies.
I'm developing burnt tips on my acropora's and my montipora plate colonies are looking terrible. First major problem in 10 years reef keeping. I could bore you with all my water quality parameters but they are spot on.
I read this article in searching for a solution, http://www.reef-eden.net/iodine_in_the_reef_aquarium.htm.
Using a salifret iodine test kit which test for iodine, iodate and iodide, I'm getting a reading of 0ppm. So I think that could be a problem hence the question about using GAC while dosing Saliferts Natural Iodine supplement.
I'm developing burnt tips on my acropora's and my montipora plate colonies are looking terrible. First major problem in 10 years reef keeping. I could bore you with all my water quality parameters but they are spot on.
I read this article in searching for a solution, http://www.reef-eden.net/iodine_in_the_reef_aquarium.htm.
Using a salifret iodine test kit which test for iodine, iodate and iodide, I'm getting a reading of 0ppm. So I think that could be a problem hence the question about using GAC while dosing Saliferts Natural Iodine supplement.
A. Grandis
Active member
The only cnidarians we can legally keep here in Hawaii are the local soft corals and zoanthids. I see a difference when not dosing iodide. I don't dose lots of it either, but there is definitely a difference when I stop dosing it.
I would think that somehow also helps on their immunization.
What about the skimmer? Should we be concern about skimmers when dosing iodide?
I don't dose iodine nor iodate.
Grandis.
I would think that somehow also helps on their immunization.
What about the skimmer? Should we be concern about skimmers when dosing iodide?
I don't dose iodine nor iodate.
Grandis.
Sounds interesting. Do you perform regular water changes?
I have been playing with iodide for about 6 years now, and know for a fact there are benefits. In my experience if benefits are to be realized they will be observed with iodide in the 10-20 ppb range. It also has to be the only limiting nutrient. This experience doesn't come free though, I have damaged or killed more than 40 different corals, so tread lightly. I notice the benefits when I add only 6 drops of 1% potassium iodide twice a week to 100L, that is only about .25 mL. The observations I see are similar to the article where corals color quickly or shrimp molt cleanly, but the planets have to line up a little bit (such as dosing right when the lights go off). I also like to give my new shrimp a few drops or a water change because a couple usually need to molt by the time they get to my house.
I tend to push things, and my most recent victim of this experimentation (I think) is this Acropora. Both this Acropora and a pocillopora got a bulge. The pocillopora's bulge went away but this remains unchanged. I wouldn't be playing with these frags in this BB QT without prior practice and you can see I still messed up a little at less than half of a dose recommended on ESV's supplement.
I have been playing with iodide for about 6 years now, and know for a fact there are benefits. In my experience if benefits are to be realized they will be observed with iodide in the 10-20 ppb range. It also has to be the only limiting nutrient. This experience doesn't come free though, I have damaged or killed more than 40 different corals, so tread lightly. I notice the benefits when I add only 6 drops of 1% potassium iodide twice a week to 100L, that is only about .25 mL
. The observations I see are similar to the article where corals color quickly or shrimp molt cleanly, but the planets have to line up a little bit (such as dosing right when the lights go off). I also like to give my new shrimp a few drops or a water change because a couple usually need to molt by the time they get to my house.I tend to push things, and my most recent victim of this experimentation (I think) is this Acropora. Both this Acropora and a pocillopora got a bulge. The pocillopora's bulge went away but this remains unchanged. I wouldn't be playing with these frags in this BB QT without prior practice and you can see I still messed up a little at less than half of a dose recommended on ESV's supplement.
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I think it very unlikely that iodine will help, but it is easy enough to try dosing some and see.
Iodine is rapidly depleted in most aquaria, GAC or not, since many creatures such as micro and macroalgae take it up. So it needs to be added frequently if the goal is to maintain a natural level (which I do not generally recommend as useful). In mine it was depleted from NSW levels to none detectable in just a couple of days.
A. Grandis
Active member
I'll take that as a no.
Yes, ~10% weekly water changes.
I dose .5 ml of iodide 3 times a week.
Grandis.
