How do you know how much and how often to dose trace elements?

Tbg299

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I recently purchased Tropic Marin A+ and K+. My total tank volume is 80 gallons and the recommended daily dose on the container just seems like a lot to me as are most of these additives. How do you know how much your corals actually need? Also is it possible to overdose on trace elements?
 

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It is hard to tell how much your corals need. You can get test kits for some of these (such as potassium but tropic marin trace doesn't contain it for some weird reason). I have a salifert iodine and potassium test. Others use ICP to get a better picture. I don't do water changes so these things get drained in my tank (potassium very heavily). These are the only minor or trace kits I have.
 
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Lavey29

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First : why do you think you need trace elements? Is your salt lacking in these or your corals not doing well?
True, weekly water changes should suffice. If you go long between changes and have lots of corals then I can see where trace is needed.ICP test really the only way to determine whether you need to supplement.
 
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mehaffydr

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You should always only dose your aquarium if you have a test that shows you need to. The chances of you getting it right just randomly dosing because a bottle says so are slim to none. I would go with an ICP test and see if you really need anything before adding.
 
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LordofCinder

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you have to test everyday, you can actually watch some elements decrease on a daily basis. For example, my alk decreases by about .6 every single day, that way I can figure out how much to dose.

You should be testing for a few months IMO to learn what your tank likes, to learn how fast elements are consumed, learn how water changes impact the tank.... then, when you know your tank properly you can make a judgement if dosing is right for your tank, or if water changes are sufficient.

Different animals consume differently elements at different paces, so every tank is different, no one can tell you how much to does in your tank.
 
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Randy Holmes-Farley

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I recently purchased Tropic Marin A+ and K+. My total tank volume is 80 gallons and the recommended daily dose on the container just seems like a lot to me as are most of these additives. How do you know how much your corals actually need? Also is it possible to overdose on trace elements?

In the absence of any measurements (which is going to be time consuming and expensive to determine), I'd stick to the recommended amount at the recommended interval.

The liquid volume added has nothing to do with the amount of each element added (that is, judging whether it is a lot or a little by the mL dosed is not useful), and Tropic Marin has presumably based the amounts on typical reef tank consumption rates.
 
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Tbg299

Tbg299

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In the absence of any measurements (which is going to be time consuming and expensive to determine), I'd stick to the recommended amount at the recommended interval.

The liquid volume added has nothing to do with the amount of each element added (that is, judging whether it is a lot or a little by the mL dosed is not useful), and Tropic Marin has presumably based the amounts on typical reef tank consumption rates.
I bought a Triton lab sample kit which I'm assuming will tell me what trace elements are in excess or deficient
 
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Randy Holmes-Farley

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I bought a Triton lab sample kit which I'm assuming will tell me what trace elements are in excess or deficient

Yes, it can be helpful, but not perfect. It is a one time snapshot so only gives what is needed once. Whether that dose is ever needed again needs more testing.

I'd also be wary of anything except big differences in trace elements since accuracy may not be perfect, and some elements cannot be detected at natural levels by ICP-OES (as opposed to ICP-MS). Iron, for example:


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 [edit: that part is no longer true, I've seen some], 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.
 
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PatW

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Some trace element systems tag the trace element additions to your ALK or Ca consumption. The idea here is that as corals build skeletons, they will absorb a certain amount of trace elements.

But it is all a bit of groping in the dark. Most of the trace elements do not have tests that are useful for the reefer. And most reefers do not have access to an analytical chemistry lab.

Salt mixes have the trace elements that corals need. So water changes are a nice brute force method that is very effective.
 
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Excuse my ignorance, how is this possible? it goes against everything i'm reading.


The only time I do it is when I'm cleaning my sump or one patch of the tank with low flow. I use carbon, socks, and a refugium as my export, and dose everything else back in.
 
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nano reef

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I’ve tried but not really …I’ve dosed Iodine and witnessed some positive signs in softies but I’d be lying if I claimed to know what I’m doing …
eitherway I’ve never seen deaths caused by lack of some trace element …
just one option but I’d skip it
I want to start dosing iodine! Someone posted pics of his zoas that had crazy long lashes and he said he dosed iodine and aminos. I just order brighwell aminos and want to start dosing that and I have lugols iodine. The instructions are so confusing on lugols! Do you dose that and did you test your iodine levels first?

I dont have an iodine test kit. Do you think I need one Because I just placed an order and could probably add to it and dont feel like spending the money on 2 icp tests for both tanks! Do you mind giving me some pointers on dosing iodine?
 
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Randy Holmes-Farley

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I don’t know if iodine dosing is useful, but it’s a fine experiment to try. I never found it useful.

Bear in mind that Lugols is an unnatural and reactive form of iodine that may impact the bioavailability if other trace elements such as iron by oxidizing them.
When folks claim an effect with Lugols, it isn’t clear whether it is the iodine or dosing an oxidizer that had the effect.
 
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