Red Sea Iodine test kit

[pseudorand]

Does anyone have any hints on the Red Sea Iodine test kit?

The kit works by adding two liquids to each of a sample of RO/DI and tank water and then reading the color of the tank water when the RO/DI water matches a color on the chart -- the RO/DI water is a timer for the reaction. However, the RO/DI water always matches the "standard" color as soon as I add the reagents (not 5-15 minutes later as stated by the instructions), and neither vial seems to change color no matter how long I wait.

Today the RO/DI "standard" was darker than the color chart. I assume I must have put tank water in the "standard" vial and RO/DI in the "standard" vial by mistake, but I could swear I double-checked that as I was putting them in.

Basically, I don't trust a test kit that doesn't seem to work as the instructions say. Has anyone else had similar experiences with this kit?

 

[Shirak]

I have the kit and have used it a few times. No clue if it's giving a reasonably correct result. I can see a color change but it's more on the order of a few minutes not the 5-15 stated on the instructions, which gives me pause also. Particularly since I just do the test at room temperature instead of trying to warm both to aquarium temperature which is goofy since they just need to be the same temperature.

You could try putting double the iodine reference standard into the RODI vial just for kicks to see how dark it is after adding the other reagents.

 

[Randy Holmes-Farley]

If chlorine is in your RO/DI, that might read as iodine.

 

[pseudorand]

So I think I forgot to put the power in the RO/DI. I re-ran the test and got 0.06ppm -- just like I always do. This is particularly strange because the dosing instructions on red sea colors say you can dose based on calcium consumption. I can measure potassium and iron go up and down as I dose (or neglected to), but iodine never changes. If iron and potassium decline when I don't dose, shouldn't iodine do the same?

 

[Randy Holmes-Farley]

So I think I forgot to put the power in the RO/DI. I re-ran the test and got 0.06ppm -- just like I always do. This is particularly strange because the dosing instructions on red sea colors say you can dose based on calcium consumption. I can measure potassium and iron go up and down as I dose (or neglected to), but iodine never changes. If iron and potassium decline when I don't dose, shouldn't iodine do the same?

Iodine depleted rapidly (0.06 ppm to undetectable in a few days) in my tank and had nothing to do with calcium consumption. That claim is spurious, IMO, since algae is a big consumer of iodine.

IME, dosing iodine is not beneficial.

You mention iron. I personally do not recommend the super high levels of iron needed to detect with their kit. IMO, they may recommend such a high level only because that way it can be detected with their kit.

This is from an article of mine:

Iron (Fe). The natural iron level varies a lot with depth, but surface seawater may have only 0.006 µg/L. The Triton LOD = 0.3 µg/L. I dose iron, and when I dose it I boost iron to roughly 1-2 µg/L, which would be detectable. This sample was taken more than a week after the last iron dosing, and none was detected as it gets depleted in the meanwhile. I’ve not yet seen a Triton test result for a real aquarium sample that had detectable iron, but that doesn’t mean these tanks are necessarily deficient. Iron is also a case where the form is critical, and ICP cannot distinguish form. Binding to organic matter, for example, can alter the bioavailability of iron.

 

[pseudorand]

Iodine depleted rapidly (0.06 ppm to undetectable in a few days) in my tank and had nothing to do with calcium consumption. That claim is spurious, IMO, since algae is a big consumer of iodine.

IME, dosing iodine is not beneficial.

You mention iron. I personally do not recommend the super high levels of iron needed to detect with their kit. IMO, they may recommend such a high level only because that way it can be detected with their kit.

This is from an article of mine:

Iron (Fe). The natural iron level varies a lot with depth, but surface seawater may have only 0.006 µg/L. The Triton LOD = 0.3 µg/L. I dose iron, and when I dose it I boost iron to roughly 1-2 µg/L, which would be detectable. This sample was taken more than a week after the last iron dosing, and none was detected as it gets depleted in the meanwhile. I’ve not yet seen a Triton test result for a real aquarium sample that had detectable iron, but that doesn’t mean these tanks are necessarily deficient. Iron is also a case where the form is critical, and ICP cannot distinguish form. Binding to organic matter, for example, can alter the bioavailability of iron.

Interesting. However, I do get different iron results with the red sea iron test depending on how much Brightwell Ferrion and/or chaetogro I dose. I would expect those both have chelated iron. The red sea iron test is not a titration test.

Anecdotally, the Brightwell supplements do make my chaeto grow faster, which does help control algae. That's the results I expect based in conventional wisdom, so I certainly wouldn't swear by my experience. But I'm too afraid of algae to stop maintaining my iron level since that did at one time correlate with less algae in my tank. Unfortunately I suspect such fears account for the majority of things I do to my tank.

 

[Randy Holmes-Farley]

Interesting. However, I do get different iron results with the red sea iron test depending on how much Brightwell Ferrion and/or chaetogro I dose. I would expect those both have chelated iron. The red sea iron test is not a titration test.

Anecdotally, the Brightwell supplements do make my chaeto grow faster, which does help control algae. That's the results I expect based in conventional wisdom, so I certainly wouldn't swear by my experience. But I'm too afraid of algae to stop maintaining my iron level since that did at one time correlate with less algae in my tank. Unfortunately I suspect such fears account for the majority of things I do to my tank.

I'm not sure I understand. I wasn't saying anything about a titration test. I don't know of any titration test for iron. I was talking about the very high levels needed to detect with any kit. Too high, IMO, unless your purpose is something beyond iron supplementation, such as iron phosphate precipitation.

 

[pseudorand]

As a follow on to this thread, I got an ipc that put me low on iodine. I have various tank issues, mostly with all corals except palys, zoas, euphilia and xenia dieing. But I have no algae problem anymore. Perhaps it used all the iodine and now can't survive. That would be consistent with Randy's observation that algae consumes lots of iodine.