# BBA problem and low nitrates



## tubamanandy (14 Jul 2015)

Having an issue with BBA over past weeks in my hi-tech setup.

I've started to dose Easycarbo at standard dosing levels over past week or so in addition to my pressurised CO2 which is definitely helping.

Took a few Nitrate readings over past week and, assuming my testkit is working, I have very low levels yet I'm dosing standard amount of EI ferts on alternative days.

Any ideas why my NO3 is so low and should I increase the amount of EasyCarbo I dose ? (not sure how toxic it is)


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## dw1305 (14 Jul 2015)

Hi all,





tubamanandy said:


> Took a few Nitrate readings over past week and, assuming my testkit is working, I have very low levels yet I'm dosing standard amount of EI ferts on alternative days.


 It is the test kit. Nitrate is problematic to test for, even with analytical quality equipment.  

Most colorimetric tests rely on the formation of a coloured insoluble compounds, but this is difficult with nitrates, because nearly all nitrate salts are soluble. Have a look at  <"Mg+K+Fe=no NO3???">.

cheers Darrel


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## tubamanandy (14 Jul 2015)

Ok, can I test this out ?

I have the dried powders that I use for making up EI - I'm certain one of them is Potassium Nitrate.

Can you tell me basically how to make up a small stock solution (eg. 200 ml) of Potassium Nitrate at say 50mg/ltr - I can then `test` it with my NO3 test kit & see what result I get.

I know it wont be accurate but I would at least hope to get some sort of reading


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## ian_m (14 Jul 2015)

Use this to work out values. Remember to use RO or distilled water, don't want nitrates in tap water interfering.

http://yanc.rotalabutterfly.com/
eg set tank size to 100litre, select DIY, select KNO3, select dry dosing, select "the result of my dose" and select 1gr. This will give 6.13ppm.

If you can measure small enough might want to use say 1litre and 10mg which will give you 6.13ppm.

Or 16mg in 1litre water give 10ppm.


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## tubamanandy (14 Jul 2015)

Wow, thanks very much for that - REALLY helpful.

Love playing around with the amounts etc


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## ian_m (14 Jul 2015)

What you really need to do is make say 10cc with 1.6gr giving 10,000 ppm (assuming it dissolves, try 0.16gr).

Then take 1cc of this to 9cc of water to give 1,000ppm...then repeat 1cc to 10cc to get 10ppm. I think my maths is right....


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## Christos Ioannou (14 Jul 2015)

ian_m said:


> http://yanc.rotalabutterfly.com/


Please be careful as I noticed that when setting up a *solution*, for ESTIMATIVE INDEX method, changing the dosage_ "each dose is"_ value will NOT change the grams of kno3.


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## dw1305 (14 Jul 2015)

Hi all, 





ian_m said:


> What you really need to do is make say 10cc with 1.6gr giving 10,000 ppm (assuming it dissolves, try 0.16gr). Then take 1cc of this to 9cc of water to give 1,000ppm...then repeat 1cc to 10cc to get 10ppm. I think my maths is right....


 That is the one, "serial dilution". 

If you look in the <"linked thread"> there are the workings, and an explanation of how to construct a standard curve.

cheers Darrel


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