Despite API reputation, the Chemicals in the test kits are actually good

[Reefahholic]

API doesn’t sell a Mag kit?? Heh

 

[TangerineSpeedo]

This whole time I’ve been thinking ATI was just freshwater crap. Who would have thought. Might have to pick one up. If I could get a Cal and Mag test within 5-10 ppm I’d be thrilled to death. Surprisingly, I’m having more trouble with those two than anything else.

On the Cal with API I treat it like a titration test. couple drops, swirl, when you get close, one drop, swirl. The instructions say just count the drops till it changes to blue, but the way I do seems to work out well.

 

[MnFish1]

On the Cal with API I treat it like a titration test. couple drops, swirl, when you get close, one drop, swirl. The instructions say just count the drops till it changes to blue, but the way I do seems to work out well.

FYI - You have misread the instructions (But your way happens to be the correct way). The instructions say: "Holding the bottle vertically, add Calcium Test Solution Bottle #2, drop by drop to the test tube until the solution changes from pink to the blue endpoint. Be sure to count the number of drops added. Cap and shake the test tube between drops."

 

[Timfish]

Over a decade ago DFMAS conducted a comparison of different test kits. A couple test kits stood out as inaccurate but neither where API. Significant factors in differences between results include tester's interpritation of results and testing conditions (lighting). (I settled on API's alkalinity a long time ago for ease of use and price. When I got my Hanna alkalinty I checked it against a friend's kit and using the same sample of water and using both sets of reagents in both testers I got 4 numbers that varied by .9 dKH.) I saw this mentioned in a post years ago and it seems like good advice - try different test kits and tester to see what is your preference to use and don't rely on any single test if there's questions about any potential issues and compare new to old test kits/regents to be sure there's been no degradation.

Here's DFMAS pdf they had posted for a long time. It was before digital testers became commonly available for reefers so no digital testers were included.

 

[taricha]

Here's DFMAS pdf they had posted for a long time. It was before digital testers became commonly available for reefers so no digital testers were included.

Whoa! That's excellent. I hadn't seen it before.

 

[BeanAnimal]

I purchased a reefbot lab. Have been through maybe 2 dozen kits of various brands in and out of the bot. I can say, in my experience, the RedSea Pro stuff has not been great. API KH (given 1 dkh resolution) is closer than the RedSea, the same with API calcium vs RedSea. Magnesium has been better with RedSea with manual tests, but not in the bot.

 

[SteveMM62Reef]

I purchased a reefbot lab. Have been through maybe 2 dozen kits of various brands in and out of the bot. I can say, in my experience, the RedSea Pro stuff has not been great. API KH (given 1 dkh resolution) is closer than the RedSea, the same with API calcium vs RedSea. Magnesium has been better with RedSea with manual tests, but not in the bot.

The only way I can get consistent results with Red Sea’s Magnesium Test, is to use a magnetic stirrer.

 

[EeyoreIsMySpiritAnimal]

The only way I can get consistent results with Red Sea’s Magnesium Test, is to use a magnetic stirrer.

I get distracted counting to 15-Mississippi and forget what drop I'm on, lol!

 

[Jeffbear]

This topic is @Dan_P 's baby - I'm just running with it. Dan will even go further than I will and use some of the API kits that I won't mess with (NO3, PO4).

It's widely claimed that API tests can't be trusted and any values reported by API should be ignored until the hobbyist throws them in a trashcan and a more expensive test kit is purchased.
But when you measure the color response of these test kits to carefully made stock solutions of known concentration - you find that API kits perform exactly as they should in theory - forming color linearly proportional to the concentration.
I wanted to illustrate this by demonstrating the colorimetric performance of Total Ammonia, Nitrite, and High Range pH tests.

Here's API total ammonia test

Tightly linear over the range [0 - 2ppm]. The reagent amounts and ratios are tweaked a bit from the API box instructions for the range and the volume that I want to work with, but all the reagents are API. And whatever box of reagents I grab the performance is the same.


Next is the Nitrite - NO2 test.

With the recipe I'm working with, it stops being perfectly linear around 1ppm NO2 and above, so I use this when working with samples between [0 - 0.7ppm]. Above 1ppm, it still gets darker pink, just not in a clean linear way (at this reagent ratio).

And finally, here's API high range pH.
The pH test is a color indicator that's phenol red or very similar - it responds very well over the entire plausible range of saltwater pH. Here's the absorbance spectrum of the indicator in saltwater from pH of less than 7.0 to above 8.6.

The plot is showing the spectral data, but each of those colors is easily naked-eye distinguishable by comparison as well.

So if you do a ratio of the left peak and right peak absorbance and plot the log of that vs what a calibrated pH meter reads in the same solution you get this...

The log of the absorbance ratio is tightly linear to what my calibrated pH meter gives - within 0.05 pH units. (This means pH can be measured by recording color and no probe/calibration solution required, which is convenient sometimes.)

In all these examples, the technical details are unimportant, or at least the topic for another thread. What matters is that in all cases the API reagents are doing exactly what you want a chemical reagent to do. They have a repeatable, easily distinguished color response that is linear to the concentration of what you want to measure.

Here's an absurd example to drive the point home about the gap between how low the trust is of API vs how consistent the performance actually is.

I found this in a box in my garage: From the Lot numbers and the copyright info on the box and printed inserts - it was made in 2003.


So, how well does this 20yr old API ammonia kit work?
I used both API kits made 20 years apart to measure the same 0.0 and 1.0 ppm total ammonia saltwater solutions.

Pic taken at around 10 minutes - colorimetric measurements were made at around 30 minutes and I was a little shocked to see both kits gave completely identical results. ( I expected that the chlorine solution in reagent 2 would have lost its potency, but I guess the bottle was well sealed ... for 20 years. lol)


So when we say API results are "trash" etc (and there are some nonsensical results from API tests posted), we should probably talk about what we mean by that, and why they might be bad - because the chemistry is solid.

So telling somebody to go use a different set of chemicals to do the same thing seems unlikely to give a better result if the chemicals weren't the problem in the first place, right?

Dr. Wellfish says "Your garbage test results aren't my fault."

[Disclaimer, I don't love all API kits: NO3 and PO4 have too much lot to lot variation - so I'll always opt for hanna / red sea there.]

Duuude. This is what I needed to see! I just double checked a failing PH probe with an api high range. It matched (color between 8.2 and 8.4) what my back up calibrated Hanna hand held was telling.

 

[brandon429]

There are still false ammonia alert threads being created using api kits

I'm not sure its entirely the kit or reagents at fault, may not be. But somewhere between running the test and discerning if emergency action is needed api and red sea are causing all the alert posts. The worst seneye reading I had seen in the last 100 was posting. 04 ppm nh3 which is still below actionable level especially at day 25 after cycle began using ammonia and bottle bac. Api and red sea alerts are trending 2.0-8.0 in all the searchable examples. By a landslide I make the case seneye is a better tool for the masses if ammonia measurement is required.


There are easily auditable cycling threads that make ammonia testing not required for any type of cycle. We know how many days a given method takes to cycle and pass a seneye audit but api never gave any of that info in its searchable pattern wake. It fails every public vote page and is implicated with somehow misunderstanding with the masses

Api kits caused more setback in reefing cycling science than any factor the hobby has known

In the hands of pros, levels and test procedures ran by pros, api can be an accurate and powerful tool.

Dr Reef did his first big bottle bac thread solely with api proofing it was impressive.

But the masses? Chaos on file.

They may need a different instruction manual to improve ability to wield the kit accurately

 

[BeanAnimal]

But somewhere between running the test and discerning if emergency action is needed api and red sea are causing all the alert posts.

"API" and "Red Sea" likely account for 99% of the test kits sold to new hobbyists, as that is what most LFS sell and promote to new hobbyists.

New hobbyists and introduction to the nitrogen cycle and problems and questions go hand in hand, as does learning to use a test kit and the errors that come along with it. Would therefore most of the the "alert posts" not be attributed to those two brands?

If you gave every new hobbyist a kit made by XYZ, I would expect most the "alert posts" (whatever those are) to be from XYZ kit users.

Why take this thread into cycling, seneye, work threads, bottle bac etc.?

 

[Garf]

04 ppm nh3 which is still below actionable level especially at day 25 after cycle began using ammonia and bottle bac. Api and red sea alerts are trending 2.0-8.0

Why do you keep mixing NH3 and NH3+NH4? I know you really know the difference. And the last 2 ammonia high threads I've seen were related to ammonia overdoses, so claiming they were false readings would be inaccurate. Do I really have to find those threads and post links?

Edit - 2 in 1 shot, lol

Ammonia THROUGH THE ROOF

Adding ammonia and bacteria is much safer in a fishless cycle. It is a fine way to get started. IIRC, Prime will throw off your ammonia readings (high). So I don't think your ammonia is that high; the fish would likely be in distress at 8. That makes since

www.reef2reef.com

Et voila, number 2;

Insane Ammonia Spike.. 8.0 +

Okay, so try to convince my organization to invest in a digital water testing system. And I need to brush up on my cycling science. But still, it’s my fish were huddling in the bottom corner of the tank. My clove polyps completely melted overnight. My gsp and mushrooms were all closed for 2...

www.reef2reef.com

 

[tautog83]

Rip clean ,bottled bacteria ..hocus pocus .

 

[EeyoreIsMySpiritAnimal]

Rip clean ,bottled bacteria ..hocus pocus .

^^^^^^
The perfect "tl:dr" for brandon's posts!