How to make a good control solution?

[cb684]

I have been thinking about doing this for a while now. For how long a control solution using salt mix to 1.026, spiked with NaNO3 and NaPO4 would be stable to use.
I was planning to use it for ALK, Ca, NO3, PO4, K, Mg testing.
Would refrigeration help? Or just using a tight lid would suffice?
Is there a better way to do that?
I was planning to make 1 or 2 L of it, send to Triton for testing and then use for about 1 year. Comparing with the only option I know (fauna marine 100mL) that would be very cheap...

 

[JimWelsh]

Triton won't tell you the alkalinity or the NO3.

 

[cb684]

That is right. I used Triton before but I was not very concerned about ALK or NO3 so I did not realized they were not there... NO3 might be ok because I can calculate from how much I spiked the solution... As for ALK I might need to measure a few times to get an average and use that as the value for later tests.

I remember seen a thread somewhere where somebody was trying to use a hanna handheld colorimeter to read salifert NO3 test results. Do anybody remember seeing that or know if it would work?

 

[Sabellafella]

That is right. I used Triton before but I was not very concerned about ALK or NO3 so I did not realized they were not there... NO3 might be ok because I can calculate from how much I spiked the solution... As for ALK I might need to measure a few times to get an average and use that as the value for later tests.

I remember seen a thread somewhere where somebody was trying to use a hanna handheld colorimeter to read salifert NO3 test results. Do anybody remember seeing that or know if it would work?

They have it on rc using api and salifert

 

[Randy Holmes-Farley Verified Community Expert]

I have been thinking about doing this for a while now. For how long a control solution using salt mix to 1.026, spiked with NaNO3 and NaPO4 would be stable to use.
I was planning to use it for ALK, Ca, NO3, PO4, K, Mg testing.
Would refrigeration help? Or just using a tight lid would suffice?
Is there a better way to do that?
I was planning to make 1 or 2 L of it, send to Triton for testing and then use for about 1 year. Comparing with the only option I know (fauna marine 100mL) that would be very cheap...

I'd be worried that it wouldn't take much algae or bacterial growth to significantly alter the nutrient levels.

 

[cb684]

They have it on rc using api and salifert

Yes, I thought it was there. But still trying to find it. If you remember the title please share... Thank you!

 

[cb684]

I'd be worried that it wouldn't take much algae or bacterial growth to significantly alter the nutrient levels.

Refrigerating? Or I could just autoclave/filter the solution? The idea would be to aliquot in 50mL falcon tubes and use one per week.

 

[JimWelsh]

Use mercuric chloride?

 

[Sabellafella]

Yes, I thought it was there. But still trying to find it. If you remember the title please share... Thank you!

Even though revs a good man and will acually let you post something to educate , im not posting another forum on here but type in google----using hannah with salifert n03---- theres a few more i read back a while ago with using api reagent with diluting the sample with ro water sucessfully. I guess it depends on the user, if i was carbon dosing i wouldnt trust it, but if your trying to get a general idea+all the math checks out against standards and or falls inline with your other test kits would maybe be a good idea

 

[cb684]

Even though revs a good man and will acually let you post something to educate , im not posting another forum on here but type in google----using hannah with salifert n03---- theres a few more i read back a while ago with using api reagent with diluting the sample with ro water sucessfully. I guess it depends on the user, if i was carbon dosing i wouldnt trust it, but if your trying to get a general idea+all the math checks out against standards and or falls inline with your other test kits would maybe be a good idea

I understand the rules... You gave me what I was asking for: some key words to try to find it. The idea is to see if it works and bring the discussion to this forum.
Thank you.

 

[cb684]

Use mercuric chloride?

Well, I had to google to find out what you meant. Would the way it stabilizes the solution interfere with the tests we use? I am a little worried about the toxicity too.
Do you believe my idea of either filtering with a .1um filter or autoclaving the solution would not be enough to keep it for one year? What about the cold dark environment of a refrigerator? Wouldn't that be enough to avoid algae growth?