trick to testing nitrates

[iidylii]

so of course when testing your nitrates and they are off the charts you obviously aren't getting an accurate reading...I was reading online of how you can take a sample of your water and add freshly mixed saltwater to get a more accurate reading...they mentions something like you may have to perform 10 cuts to get an accurate reading?

anyways I was confused my this...anyone understand what I am trying to get at here? I assume if I were to take a small sample of my water and then add 10 times the sample with fresh saltwater I could more or less divide my number by 10 and that would be more or less an accurate reading?

is there an accurate digital nitrate reader that anyone recommends?

any easier explanations would be appreciated cuz I probably butchered that lol

 

[florida joe]

How much are you looking to spend ?? if you have deep pockets you can go with pin point nitrate meter. if you are getting off the charts readings most likely its tester error not the test. you have to preform the test EXACTLY as specified

 

[iidylii]

definitely not gonna spend $200 + on the meter

im using the salifert test and following it as closely as possible...

I just wanted to be real specific so I could maybe monitor how much my nitrates go up in say 1 week and then gauge from that how often I could do water changes to keep them right around 20ppm

 

[lmforbis]

Based on my experience as a chemist, I'd dilute the salt water with DI water. I'd do serial 1:2 dilutions. First sample no dilution then the second is the first diluted 1:2 the third is the second diluted 1:2 (= to a 1:4 dilution) the fourth is a 1:2 of the third (=to a 1:8 dilution). Just for clarity a 1:2 in my world would be equal parts tank water and DI water not one part tank water and 2 parts DI water. This is the method I use all the time to get out of range samples in range. It works very well. Once you do the series you will know where to start the next time.
The Salifert test of s pretty hard to do wrong.

 

[florida joe]

why are you not looking at ways to lower your nitrates apposed to being a slave to water changes

 

[iidylii]

well I am going to be looking for ways...but first I think it would make sense to see how quickly my trates rise in order to see how big of a problem they may be...and then yes I will see what steps I can take...

do most ppl just recommend a scrubber of some kind? other then that I have a 20 gallon calerpa chamber in my sump and I feed my fish 2 times a day a pretty small amount...my lights are on about 12 hours a day I have one kessil 150 on a 93 gallon cube tank...idk what other suggestions there might be?

 

[2quills]

Could just get a high range test like API and use Salifert to test low range.

Otherwise Imforbis, suggestion of continually diluting the sample in half until you get to low ranges for your salifert kit sounds pretty logical.

 

[iidylii]

no worries...my salifert test goes to 100 and my water came in at 75ish...I assumed it was gonna be off the charts because it has been months since I have done a water change...had a real busy time in life lately so I have slacked off on tank maintenance...my trates must not rise all that fast seeing as they haven't spiked off the charts from going a few months without changing water...but I will now start changing water weekly and taking notes on readings to see exactly what the trates are doing...

 

[iidylii]

I was also just reading up on activated carbon if it helps with nitrates and from what I found it does not...I haven't used activated carbon in my sump in at least 6 months...this is something I also should probably start dosing again as well...

 

[2quills]

While I can't confirm because I haven't gone out of my way to test the theory myself I've read some fairly convincing anecdotal evidence that API is less reliable at low range but better at high range.

And visa versa for Salifert. Better at low range and less reliable at high.

Just throwing that out there.

Carbon is good for a variety of reasons IMO.

 

[iidylii]

Not to get to much off topic but is it possible to use carbon to much...for example is it good to do a month on and a month off of carbon and repeat or is it just fine to dose constantly

 

[lmforbis]

I use carbon all the time, change it out every 2-3 weeks. I haven't seen ant negatives but I have always done it so I can't make any comparisons.

 

[2quills]

Are you actually dosing or using granular carbon?

And yes they both can effect nitrates indirectly.

Dosing organic carbon for instance feeds the bacteria that consumes nitrate.

Granular carbon (charcoal) helps remove organic compounds which can lead to nitrates.

 

[iidylii]

No I am not currently dosing or using granular carbon for at least 6 months now...I was more just curious if it would help or hurt the nitrates situation

 

[2quills]

My thoughts are that gac does have an effect.

But I doubt the discontinuation of its use solely would cause nitrate to go off the charts.

Carbon dosing on the other hand is another story.

.02