Dosing calculations double check

[Kirkfrey]

A few weeks ago I got back my ICP test and a few things were lower than I wanted. Manganese was undetectable so I wanted to start with that, I dosed manganese to bring what I thought would bring them back into spec and retested last week. I just got that back and its still undetectable. I wanted to double check my math and logic here to make sure I am not missing anything.


I am using Reef Lab manganese which states that dosing 1ml will raise 100L of water by 2ug’s. My target is to get to ug/L in a 314G total volume tank.


So here is my math:
314G = 1200 L
I want to raise Mn from 0 to 1ug
Dosing 1 ml will raise 200L to 1ug to get to the desired level
1200L total / 200L = a dose of 6 ml

Is that math right? I think it is

The initial test had undetectable Mn, and a test a week later after dosing was undetectable, I am assuming that my tank is consuming greater than 6ml per week of Mn.


Does that logic hold?

My next step is to dose 12ml and retest again to see if I can start to figure out the actual consumption rate.

The ATI ICP tests are now turning around pretty quickly, I sent my sample on the 11th and got results today the 19th.

 

[KrisReef]

I would get a new bottle of Mn to start. If you saw zero move to zero then you may have added zero, which suggests to me the possibility that your bottle is compromised, not that your tank is consuming that much, but perhaps it is?

Otherwise, your math looks good for proper dose additions. GL

 

[Kirkfrey]

Ok. It is brand new. I’ll see if lfs has any (they don’t before) and try a different brand.

 

[KStatefan]

I add 0.1µg/l per day and after 5 weeks i went from 0.06 µg/l to 0.19 µg/l. It seems like it either get consumed quickly or my dosing chemical does not provide the stated increase.

 

[Randy Holmes-Farley Verified Community Expert]

I add 0.1µg/l per day and after 5 weeks i went from 0.06 µg/l to 0.19 µg/l. It seems like it either get consumed quickly or my dosing chemical does not provide the stated increase.

Manganese is rapidly stripped. A small bit of algae growth each day can tank up a whole tanks worth.

 

[Randy Holmes-Farley Verified Community Expert]

A few weeks ago I got back my ICP test and a few things were lower than I wanted. Manganese was undetectable so I wanted to start with that, I dosed manganese to bring what I thought would bring them back into spec and retested last week. I just got that back and its still undetectable. I wanted to double check my math and logic here to make sure I am not missing anything.


I am using Reef Lab manganese which states that dosing 1ml will raise 100L of water by 2ug’s. My target is to get to ug/L in a 314G total volume tank.


So here is my math:
314G = 1200 L
I want to raise Mn from 0 to 1ug
Dosing 1 ml will raise 200L to 1ug to get to the desired level
1200L total / 200L = a dose of 6 ml

Is that math right? I think it is

The initial test had undetectable Mn, and a test a week later after dosing was undetectable, I am assuming that my tank is consuming greater than 6ml per week of Mn.


Does that logic hold?

My next step is to dose 12ml and retest again to see if I can start to figure out the actual consumption rate.

The ATI ICP tests are now turning around pretty quickly, I sent my sample on the 11th and got results today the 19th.

You cannot determine doses of rapidly depleting chemicals (such as iron and manganese) using icp spread out over an extended period, and you don’t want to add huge amounts to make natural levels show up a month later.