How to properly read API nitrate test

[Djplus1]

I'm sure everyone here is familiar with these tests. My question is when comparing colors, are you supposed to place the vial ON the white next to the color to judge reading or hold it a couple inches off of the white? Or maybe even further away?

 

Let's say, the color is much, much darker if you hold on the card.

[Djplus1]

This looks like 80 if I press up against card.

 

This looks closer to 40 if I hold it about a 1/2" off the card.

[FrankieGee]

I always wondered the same thing. I usually hold it to the card for my results and I use test strips to verify my results. Comes out almost the same. Someone recommended Salifert test kits so I'm going to try it out this weekend.

[netpez]

I use API for common use. I hold it a bit away from the card for a more accurate reading in the light. If I notice the test is higher than my norm, I will go and double check with my salifert which I think is much more accurate, but I use sparingly because salifert can be a little bit more expensive.

Edited June 14, 2013 by netpez

[Jason Rhoads]

What I try to do (and this may not be correct) is to put the tube over each color block until I find one that disappears (because the color matches so closely that they are indistinguishable) when the tube passes over the block.

 

 

Great question though, they are hard to determine sometimes -see my signature

[netpez]

What I try to do (and this may not be correct) is to put the tube over each color block until I find one that disappears (because the color matches so closely that they are indistinguishable) when the tube passes over the block.

 

 

Great question though, they are hard to determine sometimes -see my signature

 

Gotta agree with you on these color comparison cards... they drive me nuts... half the colors look all the same to me... that is why I prefer some of the tests like salifert uses where it changes from 1 color to another and you measure the syringe

 

I wish salifert would change their nitrate test to the same concept.

[Djplus1]

I'm using Red Sea for reef pertinent stuff. I'm basically trying to kill off the API test before I get something else. But I will say, even the higher end test kits drive you insane. For instance Red Sea's Alk test changes from blue to orange-ish pink. The problem is it turns into a light purple first and that is close to the final color, so depending on where you feel the pink is pink enough it could be 2-10 drops of a difference.

[zygote2k]

I've been testing water for nearly 20 years now and if you want my opinion, there are only 2 good reliable test kits that aren't confusing and are super accurate- Salifert and LaMotte.

I don't understand why someone would spend hundreds of dollars on livestock that depends on accurate test results and they cheap out on junk test kits like API and the others that fall into the same category.

Buy it once, and buy it correctly.

[swimmatte]

I've been testing water for nearly 20 years now and if you want my opinion, there are only 2 good reliable test kits that aren't confusing and are super accurate- Salifert and LaMotte.

I don't understand why someone would spend hundreds of dollars on livestock that depends on accurate test results and they cheap out on junk test kits like API and the others that fall into the same category.

Buy it once, and buy it correctly.

I think the issue is, when people (like me) start out, they don't realize that the API kits are junk because every LFS and their mother sells them. And for the $40-$50 price tag that most LFS put on them, you'd think they would be decent. Eventually, I believe most people switch to a better kit.

[countryboy]

SALIFERT! might cost more but the results are worth it!

[Djplus1]

I'm real happy with the Red Sea tests as a whole. Does Salifert make a better nitrate test or does Lamotte or Red Sea? Basically, the only test that I need is the nitrate, which I currently only have API for, because I apparently am not on Zygote2k's level and didn't buy Salifert or Lamotte, when I graduated elementary school.

[Origami]

Hold it away from the card. If you hold it against the card, the shadow from the tube influences your perception of the color.

[netpez]

Hold it away from the card. If you hold it against the card, the shadow from the tube influences your perception of the color.

 

Coming from the trustworthy man, who taught me to read the instructions on my salifert test, so that I wasn't reading 100+ on my nitrate test  

[lnevo]

Hold it away from the card. If you hold it against the card, the shadow from the tube influences your perception of the color.

Agreed. Looks like 40 to me.

[treesprite]

I went through this a few years ago regarding the API tests. I can't remember the exact number, but basically, about an inch in front of the white area, in bright light.

 

I recently got Sea Chem nitrite/nitrate kit (along with others), which I like. The Sea Chem kits come with vials of controls to compare to make sure you're doing the test properly (for example, the nitrate test control will show a result of 10). 

[hawkfish01]

Yeah i got api too.. Hate them! Going seifert or red sea when gone...

[Djplus1]

OK, as if my nitrates weren't giving me enough of a headache. I can honestly say, this is the hardest test to get any consistency on. 

Today I ran three different Nitrate tests, results as follows.

 

API-Somewhere around 20

Red Sea- Ran normal, shows high result >10, when retested at high value instructions, I am in color range, between 4 or <4????

Elos- Appears to be 1

 

I can't just assume that the API is wrong or the Elos is right, just because someone says one test is better than the other, and I'm not even sure what to think of my Red Sea result and have contacted them already.

 

Any reason for the discrepency? Or are we all sheep that believe that since the tests that we were told to buy tell us something, it must be right? If so, anyone want to buy my new brand of Saltwater test kits? My colors will always be what you want them to be, for perfect results! (it will actually just be a magic 8ball with the words good and bad).

[YHSublime]

I've been testing water for nearly 20 years now and if you want my opinion, there are only 2 good reliable test kits that aren't confusing and are super accurate- Salifert and LaMotte.

I don't understand why someone would spend hundreds of dollars on livestock that depends on accurate test results and they cheap out on junk test kits like API and the others that fall into the same category.

Buy it once, and buy it correctly.

 

 

I think the issue is, when people (like me) start out, they don't realize that the API kits are junk because every LFS and their mother sells them. And for the $40-$50 price tag that most LFS put on them, you'd think they would be decent. Eventually, I believe most people switch to a better kit.

 

Rob, I would venture to say because of the exact same thing Matt said. Every single fish store sells them like they are the only options available. DJ, take a water sample to any of our vendors and I'm sure they'll test it for you.

[treesprite]

I recently got some Sea Chem tests and really like them. They come with vials of controls to check the accuracy of your tests (or how you are doing them).

[Marc Weaver]

I've used Tropic Marin, API, Red Sea Pro, ELOS, and Lamotte all multiple times.  The Lamotte 3110 is by far my favorite for repeatable, easy-to-read results.  I have not tried the Salifert, but I like the idea of their precision when looking through the vial sideways  There is currently no available titration test for nitrates in the hobbyist price range that I am aware of, unfortunately.  

 

My experiences and $.02 (if anyone cares)

API - Good for cycling a tank only, then throw away after your first few water changes indicate levels are lowering.

Tropic Marin - A little better

Red Sea Pro - Frustrating, due to the fact that if you are high range and test in the low range, you waste a test.  I went through 2 batches of reagents and the colors never closely matched the wheel in my opinion.  Also, one of the reagent bottles would constantly clog.  I believe the cadmium in it may be difficult to keep in solution and is clogging the dropper.

ELOS - It works well and is repeatable, the color comparison chart is not too bad.

Lamotte 3110 - Expensive but worth the money  Reagents are not available from many places, especially on the east coast.  I've never tried ordering from Lamotte direct, though which is in Maryland. You have to multiply their scale by 4.4, so measurements are 1.1, 2.2, 4.4, 8.8, 17.6, 26.4, 35.2, and 44.4ppm.  The color changes on the color comparator are good enough to determine values between the labeled ones.