Iodine question

[Jason72]

Hi all,

I'm stuck. I've had a problem with my green palys closing up - they haven't really been open for weeks now. All other corals, including yellow colonials, are fine. But the palys and some random zoas are curled up and closed.

90 Gal - Parameters:

pH: 8.1
Ca: 400
dKH: 8
Mg: 1200
temp 78
Ammonia, Nitrate, Nitrite, Phosphate all 0

I also run carbon 24/7.

Iodine is 0 (last thought of what could be going on). Been attempting to dose Lugols (approx 2-3 drops a day for fear of overdosing). Testing with SeaChem (I know, but...) test kit, still reading a 0. I'm also running the comparison test at the same time with the kit, and that is coming out at normal levels, so I know I'm not testing wrong.

My question is twofold. Should I continue to dose the Lugols and test - slowly but surely? Put a higher dose to try to raise levels? And would that likely help with the coral issue?

Second: would carbon strip iodine out of the water? I know the polyps use it and can deplete, but I'm confused why I'm adding and not seeing a level increase.

Thanks in advance.

 

[JohnK]

Iodine is tricky. I'm no expert on the detials, but IIRC it's very difficult to make a test kit that works consistently and accurately. (A reading of zero makes me suspicious. A continued reading of zero after adding a supplement makes me even more suspicious....)

It's also super tricky because too much iodine is potentially VERY bad/harmful.

IMO your much better off doing some substantial water changes if your really worried about iodine levels. Again, IIRC iodine testing with hobbiest quality tests is iffy at best. Get things to near normal with water changes, then maybe work out a regular dosing plan from there if you feel you must supplement it. (Delbeek and sprung outline a way to get a dosing plan going by observed diatom growth insted of test kits in one of their books).

Articles on iodine in the reef tank
Iodine in Marine Aquaria: Part I
http://www.advancedaquarist.com/issues/mar2003/chem.htm

Iodine in Reef Tanks 2: Effects on Macroalgae Growth
http://www.advancedaquarist.com/issu...l2003/chem.htm

"
A quick exerpt from the first article;
I would strongly advise people to not try to maintain 0.06 ppm iodine using supplementation and a test kit.

Why you ask? Isn’t that what we do for most other chemicals of interest? Well, if we could easily and accurately determine the concentrations of the different forms of iodine in aquaria, then I would recommend doing just that. However, if you combine the complexities of having multiple iodine species present with the uncertainty of having hobbyists use very complex test kits that may readily yield incorrect or difficult to interpret results, the stage is set for people driving their total iodine to levels far from what they actually intended. I do not know what levels of iodide or iodate become apparently problematic to real aquaria, but the risk of overdosing in this fashion is not insignificant. Both of the ICP studies reported above found some tanks with substantially elevated total iodine levels. I have no way of knowing how those levels got there, but overdosing of a supplement is one likely way. "

 

[Jason72]

Hm - that's what I was afraid of. I had a LFS tell me that it sounds like low iodine is causing the coral issue (process of elimination) and I'm using IO, which reportedly has a just-acceptable iodine level to begin with.

 

[JohnK]

I've heard that same advice at LFSs before, but try asking whoever it is to articulate why they are saying that, then compare what you are told to the info in Randy's articles. I know I was left scratching my head wondering what various LFS people had been telling me

 

[Jason72]

Ha ha. Yeah I know what you mean. I've read, and re-read, and re-re-read all that stuff, and all I can deduce from most of what I've found is that... well... you know what they say opinions are like....

any other ideas on what might be happening in my little aquatic dungeon?

 

[wrassefan]

I would do a couple of 30% water changes....stop the carbon for a bit. Never had issues with iodine and zoas using IO. Flow and too much light are usually why my zoas have closed in the past. You could always dip the zoas in betadine as a preventative. 3ml to every liter of water and aerate will for 20-30min. Rinse and put back in med flow with low light.

 

[Jason72]

I'll knock off the carbon and see what happens. I'm pretty good about water changes the past few months, but I can't dip the corals themselves (they've grown up the side of a huge freakin rock - no way that puppy is coming out lol).

I think they started right about the time I changed my carbon come to think of it. Maybe there was something in there they didn't like... although I've always had zoa issues....

 

[stingythingy45]

I'll knock off the carbon and see what happens. I'm pretty good about water changes the past few months, but I can't dip the corals themselves (they've grown up the side of a huge freakin rock - no way that puppy is coming out lol).

I think they started right about the time I changed my carbon come to think of it. Maybe there was something in there they didn't like... although I've always had zoa issues....

I agree with the others,Jason.Probably need to take the carbon out and see how that goes.I recently had some issues with palys and zoas and found my PH was consistantly low.I've since gone to auto top-off with Kalkwasser and things are much better.

 

[Jason72]

Yep. Gonna try that tonight. They'll make it, or they won't. It's all in the Reefer God's hands now.....

 

[stingythingy45]

Yep. Gonna try that tonight. They'll make it, or they won't. It's all in the Reefer God's hands now.....

I'm sure they make it.Sometimes zoas and palys can look pretty bad and still bounce back.