Where Is The Iodine Coming From?

watdachuck · May 12, 2019

I received my water test results from Aqua Medic and can't for the life of me think of where the Iodine build up is coming from.

.68, is this a testing error?

- I use Reborn in my CaRx
- Feed Hikari Angel Formula, Rods Reef, Nori
- Dose AcroPower, Reef Roids, BRS Chili
- Soak foods with Selcon, Brightwell Angelixir

ScottR · May 13, 2019

watdachuck said:
I received my water test results from Aqua Medic and can't for the life of me think of where the Iodine build up is coming from.

.68, is this a testing error?

- I use Reborn in my CaRx
- Feed Hikari Angel Formula, Rods Reef, Nori
- Dose AcroPower, Reef Roids, BRS Chili
- Soak foods with Selcon, Brightwell Angelixir

Probably from your salt mix. It’s building up from possibly not being used by your corals whereas your corals are probably consuming other minerals faster. I believe Softies prefer iodine, so perhaps consider adding some of you see it as a problem.

watdachuck · May 13, 2019

Using IO Reef Crystals.

I do 10% weekly changes, this still seems very high even to have built up over time.

sfin52 · May 13, 2019

watdachuck said:
I received my water test results from Aqua Medic and can't for the life of me think of where the Iodine build up is coming from.

.68, is this a testing error?

- I use Reborn in my CaRx
- Feed Hikari Angel Formula, Rods Reef, Nori
- Dose AcroPower, Reef Roids, BRS Chili
- Soak foods with Selcon, Brightwell Angelixir

Are you dosing. Check contents of the stuff your dosing. I bet you find it there.

ScottR · May 13, 2019

watdachuck said:
Using IO Reef Crystals.

I do 10% weekly changes, this still seems very high even to have built up over time.

How often do you do water changes? Say your Ca is at 420 and Mg at 1200. Your corals are taking in what’s readily available to them. You do a WC and replenish. However, your salt also provides iodine as a trace supplement. Your corals (depending heavily on type you have) don’t need that much. They won’t take it in. Over time iodine stays in the column unused and accumulates to high levels. That’s my take.

However, if dosing or adding anything to your tank besides RODI, there could be numerous possibilities.

ScottR · May 13, 2019

ScottR said:
How often do you do water changes? Say your Ca is at 420 and Mg at 1200. Your corals are taking in what’s readily available to them. You do a WC and replenish. However, your salt also provides iodine as a trace supplement. Your corals (depending heavily on type you have) don’t need that much. They won’t take it in. Over time iodine stays in the column unused and accumulates to high levels. That’s my take.

However, if dosing or adding anything to your tank besides RODI, there could be numerous possibilities.

Just saw 10% weekly changes. Seems improbable that your salt would be adding to this; although probable. I’d almost ICP your water if this is a major concern.

watdachuck · May 13, 2019

ScottR said:
Just saw 10% weekly changes. Seems improbable that your salt would be adding to this; although probable. I’d almost ICP your water if this is a major concern.

I do 10% changes weekly.

I guess the next question then would be how do I remedy this. In surfing the web several references to IORC show testing for very low if any iodine.

Would additional use of carbon remove iodine?

scriptmonkey · May 13, 2019

watdachuck said:
I do 10% changes weekly.

I guess the next question then would be how do I remedy this. In surfing the web several references to IORC show testing for very low if any iodine.

Would additional use of carbon remove iodine?

Are you seeing anything crazy happening due to high iodine levels?

ScottR · May 13, 2019

watdachuck said:
I do 10% changes weekly.

I guess the next question then would be how do I remedy this. In surfing the web several references to IORC show testing for very low if any iodine.

Would additional use of carbon remove iodine?

Don’t do anything!!! Unless you see anything negative in your tank. No tank runs perfectly as what we want but your corals acclimate and adjust. Iodine is essential in a reef tank however. I’m sure you’ll be fine.

watdachuck · May 13, 2019

The only thing that is unhappy has been my birdsnest Coral which I find interesting since I considered it the hardiest in the tank. I mostly attributed that to high Phosphates however.

My only other worry is for the 4 shrimp in the tank which I know are more sensitive to high iodine, but they have been fine so far.

ScottR · May 13, 2019

watdachuck said:
The only thing that is unhappy has been my birdsnest Coral which I find interesting since I considered it the hardiest in the tank. I mostly attributed that to high Phosphates however.

My only other worry is for the 4 shrimp in the tank which I know are more sensitive to high iodine, but they have been fine so far.

Looks nice. Oddly my birds nest outlived my acros by a long shot.

scriptmonkey · May 13, 2019

watdachuck said:
The only thing that is unhappy has been my birdsnest Coral which I find interesting since I considered it the hardiest in the tank. I mostly attributed that to high Phosphates however.

My only other worry is for the 4 shrimp in the tank which I know are more sensitive to high iodine, but they have been fine so far.

@ScottR saw where I was going with my question. Worst thing you can do is to blindly chase numbers for the sake of chasing them.

But to answer your question carbon and from what I read heavy skimming can affect iodine.

But I will say again if you do not have a problem, do not go looking for one. Look at your supplements and see if you have something that is high in I that you are putting in the tank if you are concerned.

sfin52 · May 13, 2019

scriptmonkey said:
@ScottR saw where I was going with my question. Worst thing you can do is to blindly chase numbers for the sake of chasing them.

But to answer your question carbon and from what I read heavy skimming can affect iodine.

But I will say again if you do not have a problem, do not go looking for one. Look at your supplements and see if you have something that is high in I that you are putting in the tank if you are concerned.

That is my guess to what is going on is supplements. Its hidden in one or more

dbjonesjr · May 13, 2019

Water changes will not cause your iodine levels to increase. Water changes will actually decrease your iodine levels assuming the salt creates water with less than .68 ppm iodine. A good quality carbon will remove some of the iodine but like others have said if everything is doing fine then there is no reason to chase numbers.

ScottR · May 13, 2019

dbjonesjr said:
Water changes will not cause your iodine levels to increase. Water changes will actually decrease your iodine levels assuming the salt creates water with less than .68 ppm iodine. A good quality carbon will remove some of the iodine but like others have said if everything is doing fine then there is no reason to chase numbers.

Think about this: you have an ATO. Water evaporates and adds water to your tank. You remove water through a WC. You’re removing water that has been watered down. Over time, yes - your elements will increase. You’ll see fluctuations because of this.

dbjonesjr · May 13, 2019

ScottR said:
Think about this: you have an ATO. Water evaporates and adds water to your tank. You remove water through a WC. You’re removing water that has been watered down. Over time, yes - your elements will increase. You’ll see fluctuations because of this.

I can assure you that iodine will not "build up" past the level that the salt mixes at. To give a quick example:

For simplicity I will only talk about concentrations of elements and not their actual total amount in the system. A system has 100 gallons of total water volume. This 100 gallons has an iodine concentration of 0.5 ppm. A 10% (or 10 gallon) water change will be performed. The 10 gallons of water mixed with Reef Crystals hypothetically mixes water with an iodine concentration of 0.05 ppm (close to what it should mix at). When you remove the 10 gallons from the system, 10% of the total iodine in that system is removed (multiply 0.5 ppm times 0.9) to get an effective value of 0.45 ppm. When we add the new 10 gallons into the system that has a value of 0.05 ppm we can multiply that by 0.1 (the percentage of the total system it is worth) to get a value of 0.005 ppm. Therefore we can add 0.45 ppm and 0.005 ppm to get a new iodine concentration value of 0.455 ppm after the water change. However if we add and drain water from the system at the exact same time then we can use integration to find the final value of iodine concentration after the water change.

The point is that water changes with a salt mixing at the proper iodine value will decrease the concentration of iodine in the system and not increase it.