It varies depending on location.It’s really irritating they don’t just put NSW levels next to the reading.
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It varies depending on location.It’s really irritating they don’t just put NSW levels next to the reading.
Ok, so they could give a range. Something reasonable. Or an explanation for their statements of below/above normalIt varies depending on location.![]()
Interesting post by @Hans-Werner.
I have been toying with the idea of dosing Mn but unsure of the benefit. Being used quickly in the tank I suppose is one measure that it’s useful to something, but I cannot think of anecdotes where reefers think dosing Mn had positive results. The common perception is it’s good for Gonipora. And it’s on Randy’s list of things to dose.
In iron and manganese you can overdose as much as you want, most or all of it will be out of the water in just a few days. When you take your next water sample in a few weeks or months, concentrations will have dropped back to original levels, this is almost 100 % sure.
Even chasing numbers with daily dosing of iron and manganese makes little sense. You have to dose so much because of the rapid precipitation by bacteria that you will more likely harm your tank than doing good.
Manganese is used by all organisms. I do not know what levels of what forms are needed in reef tanks to give them what they want.
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Manganese in biology - Wikipedia
en.wikipedia.org
Manganese is an essential biological element in all organisms. It is used in many enzymes and proteins. It is essential in plants.
Thank you, this is in accordance with my own experience, as you have already pointed out.To piggy back on Hans' comments, I agree that Mn to me represents a real limitation of the "dose and test" approach. Much moreso than most other elements.
After watching ICP-MS on my system for months, sometimes with no Mn input, sometimes with a trace supplement (unknown Mn level), sometimes with water changes (known several ppb/week Mn input) - Mn was always depleted down to nearly the LOD of ICP-MS <0.2ppb.
Also observationally, during this time - I note more microalgae flushes of brown/green on the glass when Mn is being input vs not. That along with other things I've observed makes me think Mn is likely acting as a limiter for some photosynthetic growth.
So - yes my Mn is low. Whether I dose none, a little, or a lot - it's still essentially within plausible measurement error of zero. If I was to be determined and added so much Mn that I actually started to accumulate it to easily measureable levels somehow, then presumably exponentially growing microalgae (diatoms, etc) would multiply until they've depleted something else. That doesn't seem desirable either.
I'm not sure Natural Seawater levels as a guide is helpful in this context either. If I can add 1x or 10x or 30x NSW levels to the tank weekly and it stays just as depleted as it was with no additions, then I don't see how NSW tells me anything about how much should be going in.
Posting this because I don't have good answers. My best guess at this point is that for Mn a "target level" isn't a great idea, a target input rate (ppb/week or day) might be a more sensible approach. I have no idea what that target input rate should be, other than I can use the fact that a 10-15% water change per week on my system with my salt is adding 3-5ppb Mn per week, and that doesn't seem detrimental, and I see organism response. And Hans' point - observe the tank carefully has to be part of it.
I was thinking whether I had any basis to decide whether I like this or not, then I realized the majority of salt mixes agree with you and have more Mn than Fe. Sometimes much more.I just would add, dosing manganese is not a bad thing. In my experience dosage of manganese should be higher than that of iron.
Yes, most likely because it is such a common impurity in certain salt deposits. However, it is hard for me to see the effects of iron and manganese in water changes. Maybe water changes fill up reserves but after manganese and iron are out of the water again there is only little effect of these metals, maybe some basic supply.I was thinking whether I had any basis to decide whether I like this or not, then I realized the majority of salt mixes agree with you and have more Mn than Fe. Sometimes much more.