Nitrates In Tap Water And The Api Test Kit

[ctsv510]

I use the standard API test kit for testing my tank water, and my main tank has had problems with the nitrate level not coming down after frequent water changes. I then tested my tap water and am getting a level of 30-40 ppm consistently. I used the same kit to test spring water (0 ppm), and also water from my parent's house 8 miles away (~10 ppm). I also used this kit to test my 30 gallon tank that is cycling (orginally fillerd with spring water), and have read everywhere from 0 to 80+ ppm with that water through the course of the cycle.

Based on me getting different levels between zero and 80+ ppm from different water sources, I feel like the test kit is relatively accruate, even if it is only withhin 10 ppm or so.

I asked my water company to come test my water because I was concerned with the nitrate level, and their results show only 4.4 ppm. Now I don't expect them to immediately admit to their water being unsafe, and I am now considering having an independent environmental company come test my water to see what their results are.

So my question is....how accurate can these API tests be? How can it be 30+ ppm off of what my water company gets? I have to check the expiration date on my kit, but regardless, if I am getting readings anywhere from 0 to 80+ ppm with this kit, I can't believe that it is expired and giving false high readings EVERY time when I test my tap water.

 

[Aqua Tom]

The API Nitrate test is realy realy hard to get right. You have to shake the bottles for the exact amount of time & bash the hell out of them on a hard surface before you start the test to free up the reagent.

 

[Spurry]

Hi i read on another post some one saying the legal limit for water comps is 50ppm from the tap, my tap water is 5ppm

 

[Blubble37]

The API Nitrate test is realy realy hard to get right. You have to shake the bottles for the exact amount of time & bash the hell out of them on a hard surface before you start the test to free up the reagent.

and if you are unlucky enough you crack the bottle and hhave to buy another one...

 

[StandbySetting]

The day you can trust an API Nitrate test kit will be the day that you can trust investment bankers with the countries money...

API Nitrate kits aren't fantastic.

 

[Blubble37]

agreed, but the longer you shake the living day lights out of it the more accurate it is (to some extent anyway)

 

[ctsv510]

I shake the crap out of the bottle and the test vile every time, and always waiting enough timme for the color to fully develop. My results are consistent each time.

Hi i read on another post some one saying the legal limit for water comps is 50ppm from the tap, my tap water is 5ppm

The legal limit for tap water nitrate levels in the US is 10 ppm. What test kit do you use?

The day you can trust an API Nitrate test kit will be the day that you can trust investment bankers with the countries money...

API Nitrate kits aren't fantastic.

Is there any test kit available for nitrate that you CAN trust? What does everyone use?

 

[Spurry]

i use a nutrafin test kit as at MA i got it price matched cost me £15 there normaly about £30

 

[StandbySetting]

The Salifert Nitrate test kit is the most accurate and precise I have used so far, it is available for around £6-8

 

[Prime Ordeal]

The legal limit for tap water nitrate levels in the US is 10 ppm

No, that's the 'nitrogen in nitrate' level (i.e. it's 10ppm of nitrogen). For nitrate the limit is 40ppm.

API test kits are, at best, 'guides' to your actual nitrate level. If you want better accuracy the salifert is good because it uses titration instead of colour charts but to get better accuracy you have to pay more money and go for something like elos or JBL.

 

[Caprichoso]

I use Red Sea, it seems to be accurate.

 

[BigbruiserAl]

The Salifert Nitrate test kit is the most accurate and precise I have used so far, it is available for around £6-8

+1 best by far for home use bar none

 

[ctsv510]

The legal limit for tap water nitrate levels in the US is 10 ppm

No, that's the 'nitrogen in nitrate' level (i.e. it's 10ppm of nitrogen). For nitrate the limit is 40ppm.

I guess you're right. The water quality reports published annually by the water company do not specify that...they simply refer to the MCL (maximum contaminant level) of Nitrate allowed in the water as 10 ppm. I am reading more and I see that that is the level of nitrate tested as nitrogen. They must leave it out of the report to simplify it for the layman.

Regardless, the water company's result of testing my tap water was 4.4 ppm of nitrate. It seems as though the API nitrate test is useless and that my tap water is safe to use for water changes.

 

[Dieses Madchen]

The water company isn't going to budge on what they feel is right. I have been going around in circles with mine over the fact there is 1ppm of ammonia in my tap water. Because they say this is normal (which I doubt, cause there was no ammonia in the water 2 months ago) I have resorted to buying bottled water for my family, and RO water for my fishtanks.