# Save \$ With Your Api Test Kit

Kasshan
Since I'm a cheapskate and I think math is fun, I did not see the need to waste the chemicals in my test kit. why waste 10 drops (gtt) when just 1 gtt would be sufficient? if you have a lot of fish tanks and do frequent testing like I do every Saturday, then simply following the instructions is going to waste \$.

the API test kit recommends filling the 5mL vial to the line, but with a small syringe you can achieve the same results with simple 7th grade math: fractions and ratios

Ammonia test: 8gtt/5mL = 1gtt/0.63mL
Nitrate test: 10gtt/5mL = 1gtt/0.5mL
Nitrite test: 5gtt/5mL = 1gtt/1mL
pH test: 3gtt/5mL = 1gtt/1.6mL

Ms rose
awesome thanx for the tip+mathdone for me haha

edit to ask: what's gtt? sry I'm not well versed yet on aquarium abriviations(?spelling?)

edit #2: can you explain this as if you were talking to a child hahah? I am not dumb but am very aweful with math

Interesting! Its morning and the math isn't getting to me but I will try again later. 5ml is quite a bit for the little amount of test stuff so thank you!

mattgirl
awesome thanx for the tip+mathdone for me haha

edit to ask: what's gtt? sry I'm not well versed yet on aquarium abriviations(?spelling?)

edit #2: can you explain this as if you were talking to a child hahah? I am not dumb but am very aweful with math
I am right there with you about the gtt. I have no idea as to what that is an abbreviation for.

Simply put

test: 8drops/5mL = 1drop/0.63mL
Nitrate test: 10drops/5mL = 1drop/0.5mL
test: 5drops/5mL = 1drop/1mL
: 3drops/5mL = 1drop/1.6mL

The first set of numbers is what the instruction that come with the kit has you using. The second set of numbers after the = is where you use much less testing material in the corresponding amount of water. Drops are product, mls are the amount of water.

Doing it this way is a very good way to do it if one has multiple tanks that have to be tested often. Not as necessary when one just has one tank and only needs to test occasionally.

Ms rose
thank you so much!!!! I test 4 tanks every to every other day, so this is my new method

edit to ask: so the nitRate est you would double both numbers correct? ( this q is for ammonia as well)

mattgirl
thank you so much!!!! I test 4 tanks every to every other day, so this is my new method

edit to ask: so the nitRate est you would double both numbers correct? ( this q is for ammonia as well)
correct

bgclarke
gtt is the abbreviation for the Latin word guttae, which means drops.

Ms rose
I am right there with you about the gtt. I have no idea as to what that is an abbreviation for.

Simply put

test: 8drops/5mL = 1drop/0.63mL
Nitrate test: 10drops/5mL = 1drop/0.5mL
test: 5drops/5mL = 1drop/1mL
: 3drops/5mL = 1drop/1.6mL

The first set of numbers is what the instruction that come with the kit has you using. The second set of numbers after the = is where you use much less testing material in the corresponding amount of water. Drops are product, mls are the amount of water.

Doing it this way is a very good way to do it if one has multiple tanks that have to be tested often. Not as necessary when one just has one tank and only needs to test occasionally.
ok so I just picked up some syringes. the ml is 1, so how do I measure .63?

edit to add: nevermind I got it lol

Kasshan
gtt is the abbreviation for drops. I wrote that in the second sentence..... the mL represents the water sample, gtt represents the drops of tester solution

thank you so much!!!! I test 4 tanks every to every other day, so this is my new method

edit to ask: so the nitRate est you would double both numbers correct? ( this q is for ammonia as well)
I divided by ten. instead of ten drops(gtt) you only need to use 1 drop for Nitrate. I'm not clear on what you were asking when you said "double", lol, no further math was required. I already gave the final answers.... I guess that is why showing work is important in school. I also tutor math on the side.

wodesorel
There is one huge problem that could cause issues - if the reagents are not able to mix thoroughly within the solution inside the bottle, one drop may not contain the same ratio of chemicals as 8 drops do. Medication is similar, a larger dose pill cannot be split 8 ways, as the medication is not guarenteed to be evenly distributed and it can either cause overdoses or not enough active ingredients.

Not so much a math problem as a chemistry problem.

mattgirl
I divided by ten. instead of ten drops(gtt) you only need to use 1 drop for Nitrate. I'm not clear on what you were asking when you said "double", lol, no further math was required. I already gave the final answers.... I guess that is why showing work is important in school. I also tutor math on the side.
Except for the nitrate and ammonia test you have to add drops from 2 different bottles. So using the original instructions you would be adding a total of 20 drops for nitrate and 16 for ammonia. Using your formula you would need one drop from each bottle so 2 drops for each test.

Kasshan
There is one huge problem that could cause issues - if the reagents are not able to mix thoroughly within the solution inside the bottle, one drop may not contain the same ratio of chemicals as 8 drops do. Medication is similar, a larger dose pill cannot be split 8 ways, as the medication is not guarenteed to be evenly distributed and it can either cause overdoses or not enough active ingredients.

Not so much a math problem as a chemistry problem.

ye those are drops per bottle, so if there are two bottles, then one drop from each bottle, the ratio still stands. believe me I'm a pharmacy tech that makes IVs for adults and children. my math is NEVER wrong. chemistry is math. stoichiometry is algebraic ratios. there would no huge problem, the concentration is exactly the same and guaranteed to give the exact same results. you are just not looking at the math correctly. 100/25 = 20/5 = 4/1 are exactly the same number

I can tutor up to calculus 1

wodesorel
It is the same number, there is nothing wrong with the math. This is not a math problem. You have no guarantee from the company making the kits that the same ratio of reagents are in each drop.

david1978
Since its a liquid suspension it should be equal. Yes pills are a little different.

My only question. Since the accuracy of the ammonia test is +/- .25, would it remain that or 10× that?

-Mak-
What I believe wodesorel is saying is, especially since some bottles need to be shaken or mixed, one drop could be made up of different chemicals than what is generally inside the bottle.

For example, the bottle may contain a ratio of 3 units of chemical A and 4 units of chemical B.

The drop that comes out may contain a ratio of 3.5 units of chemical A and 3.5 units of chemical B.

By adding more drops, we increase the likelihood of getting closer to the correct 3:4 ratio.

Kasshan
It is the same number, there is nothing wrong with the math. This is not a math problem. You have no guarantee from the company making the kits that the same ratio of reagents are in each drop.
I'm sorry but you are just incorrect. But for the sake of argument, IF you were correct and the reagents were not the same ratio in each drop, then I would throw out my test kit or ask the company to refund my \$ for selling a inconsistent and unreliable product. this is a math problem that uses 7th grade math, it should not be a debate. if you don't believe me go to your local junior high and ask a math teacher.

Fanatic
Kasshan
Now, this individual is very intellectually talented, you can come up with neat things that some other people may not have thought of, especially myself. I am not a great math person, all I can do is add, substract, and blah! Thanks for submitting this great idea, many people should find it useful and apply it to their testing habits.

Kasshan
n
What I believe wodesorel is saying is, especially since some bottles need to be shaken or mixed, one drop could be made up of different chemicals than what is generally inside the bottle.

For example, the bottle may contain a ratio of 3 units of chemical A and 4 units of chemical B.

The drop that comes out may contain a ratio of 3.5 units of chemical A and 3.5 units of chemical B.

By adding more drops, we increase the likelihood of getting closer to the correct 3:4 ratio.
apologies, but you are also incorrect in your logic. chemistry and test products are not that inaccurate, if they were the company would get sued for selling a trash product. if you have a syringe that can measure 1mL and is divided by 1/10ths then you measure down to the .05mL accurately( think back to rounding 'significant figures' in math and chemistry). like I said, I offer tutoring in math and science as a side job.
from strange and offbase responses ive received from this post I am left Exasperated (face palm); you guys are making this harder than it ought to be.
dust off those chemistry/math books and focus on titration, stoichiometry, algebra, and ratios, you will see that I am irrefutably correct.

My only question. Since the accuracy of the ammonia test is +/- .25, would it remain that or 10× that?
no change, it remains the same, they are the same ratio and same concentration. because if 10/10=1 and if 1/1=1, therefore they must be the same, making them interchangeable

david1978
Was just curious on that since that's taking into consideration both minor inconsistency of batches of chemicals and user error.

Kasshan
the solutions inside the bottle don't need to be shaken. Solutions by definition are homogeneous meaning consistently uniform, that is why in the test kit they are called ''solutions'' and NOT ''tinctures" or "suspensions" one can look this up in a simple dictionary. therefore there should be no settling because it a solution. if your product is settling inside the bottle and requires shaking I would throw it out because it has gone bad.

the only other major problem would be user error.

alauruin
like I said, I offer tutoring in math and science as a side job.

That's cool, but there are other educated folks here. (I spent a lot of time earning the title "doctor.") Those pointing out the inaccuracy in a smaller dose are correct. The smaller-quantities method may work, but will result in a much larger standard error that must be considered when reading results.

wodesorel
Wow.

Yes, at least one of the bottles MUST be shaken to guarantee the accuracy of the test. Many contain small amounts of acids and other reagents that will separate or titrate out with lack of use.

Ms rose
I divided by ten. instead of ten drops(gtt) you only need to use 1 drop for Nitrate. I'm not clear on what you were asking when you said "double", lol, no further math was required. I already gave the final answers.... I guess that is why showing work is important in school. I also tutor math on the side.
I mean, because there are two bottles lol should have specified that

Kasshan
the company wants to make to make money. of course they want you follow the instructions by using larger volumes. sometimes instructions are for people that don't know any better.

and boy, if I'm wrong (which I am not), then those patients that I mix IVs are in trouble. I specialize in catching doctor/pharmacist's mistakes. I once corrected a doctor who wanted to put a concentration of 2 gallon of Vanco in 250mL, that is greater than 5mg/mL, and an inexperienced pharmacist let it get past them. it didn't get past me. I informed the pharmacist of error and made the doctor correct the dose.

if the API test kit is as inaccurate as you all claiming, then I need to throw it away in the trash and ask for my \$ back.

david1978

Kasshan
I mean, because there are two bottles lol should have specified that

ok for the Nitrate you have two bottles.
the kit instructions say to mix 10 drops from each bottle in the 5mL sample of water right? 5 is a nice round number and allows the person possibly someone with poor eyesight to be see the color clearly. plus you are pushing more product to sell by a factor of ten. divide every number by 10

vial: collect 5mL so divide by 10 = 0.5mL
bottle 1: add 10 drops divide by 10 = 1 drop
bottle 2: add 10drops divide by 10 = 1 drop

I don't know why people (especially my fellow Americans) get so confused by the metric system

"grade" is a relative term that depends on the use, often times stuff is the same product, but just goes through different kinds of bureaucratic red tape.

my chemistry teacher in HS and college professors used these test kits for lab experiments in class, they are surprisingly accurate. I still have those lab notebooks from class somewhere in storage.
the test strips that you dip. now those are pure garbage.

david1978
They are quite accurate yes but not 100%. The accuracy was from an apI customer support member. Even drop size could very from batch of bottle to batch of bottle. I'm not a chemist or a doctor but a simple heavy equipment mechanic. If we would of tried this with any of caterpillar, volvo or fords test kits they would of laughed at us and denied warranty. So in theory nothing should change but there are so many variables.

-Mak-
Nobody is disputing your math, it's obviously correct. And I think most people here understand basic high school stoichiometry and algebra. The fact that it's in the metric system is irrelevant here, and Americans are taught the metric system in every science class starting from early middle-high school.

If each bottle contains a homogeneous mixture then I agree, they would all be solutions. The ph test is probably the best example of this.
However, we don't know for sure that they are, and we know for a fact that the nitrate test bottles are not, because they require vigorous shaking before use to create that solution.

Using more drops offsets the fact that one drop may be an outlier in how well the chemicals in a bottle are mixed.

n
apologies, but you are also incorrect in your logic. chemistry and test products are not that inaccurate, if they were the company would get sued for selling a trash product.

Test kits in this hobby, including the liquid ones, can be notoriously inaccurate, but nobody is going to sue API over a \$20 fish tank test kit.

dust off those chemistry/math books and focus on titration, stoichiometry, algebra, and ratios,
you will see that I am irrefutably correct
I'm quite familiar with each one of those concepts

Kasshan
hmmmm, now who is comparing two different worlds...?
what do those kits in your occupation do you test for? for a test kit to be accurate the variables in the test equipment should be minimized for accuracy, this is called calibration, so that really isn't a good comparison. the science remains the same, whether you are an engineer, doctor, chemist, pharmacist or just some guy mixing koolaid powder and sugar into water

so using kool aide as an example the packet says mix 1 cup sugar and 1 packet in to 1 gal of water. but wait I don't want a whole gallon, I only want 1 cup. what do I do? well for the sake of argument lets say I have a scale. since 16 cups make a gallon, therefore I would only need 1/16th of a cup of sugar and only 1/16th of the packet of kool aide. see where I am going with this?

Nobody is disputing your math, it's obviously correct. And I think most people here understand basic high school stoichiometry and algebra. The fact that it's in the metric system is irrelevant here, and Americans are taught the metric system in every science class starting from early middle-high school.

If each bottle contains a homogeneous mixture then I agree, they would all be solutions. The ph test is probably the best example of this.
However, we don't know for sure that they are, and we know for a fact that the nitrate test bottles are not, because they require vigorous shaking before use to create that solution.

Using more drops offsets the fact that one drop may be an outlier in how well the chemicals in a bottle are mixed.

Test kits in this hobby, including the liquid ones, can be notoriously inaccurate, but nobody is going to sue API over a \$20 fish tank test kit.

I'm quite familiar with each one of those concepts

why would the nitrate precipitate. calling it a "solution" is clearly a misnomer then and I guess the manufacturer mislabeled it. it can also be said from a marketing and sales aspect using more drops means people will consume the product faster and at different rates making the consumer buy more when not all test bottles are used up. using my reduced ratios all the chemicals would run out close to the same time and last much longer in the long run. now if you worked for API you would you want to sell more product? is it easier to follow to instructions verbatI'm or confuse your customers with math so that stretch their product out 5 to 10 times longer. I think you overestimate the average person's retention when it comes to HS chemistry and the metric system, etc. I tutor math and science and I am no longer shocked by (what I consider basic knowledge) what the average person has forgotten and must relearn.

TexasGuppy
I'm curious.. these colors are hard to read already. Are the smaller liquid test sizes even harder to read?

david1978
The one that's most similar is our antifreeze tests. Fill the tube to the line add a couple drops and wait for the color to change. The amount of each that are added is to produce the most accurate and repeatable result. I dought it anything money wise since they give us these kits.

Kasshan
I'm curious.. these colors are hard to read already. Are the smaller liquid test sizes even harder to read?
another reason why they want you use to more volume, the easier it is to see. not everyone has 20/20 vision. think from a sales/marketing perspective and target profits. consider these factors then you will have your answer.

The one that's most similar is our antifreeze tests. Fill the tube to the line add a couple drops and wait for the color to change. The amount of each that are added is to produce the most accurate and repeatable result. I dought it anything money wise since they give us these kits.
two drops to test antifreeze for something free (probably included somewhere in the company overhead, which I'm sure some egghead like me has already reduced the cost to the most efficient increment) versus ten drops in a personal kit you have to pay \$30 for; I think that's a big difference in practice and procedure that ought to be taken into account when trying to stretch your dollar.

Dch48
Why would it say to shake the 2nd Nitrate test solution for 30 seconds if it didn't need to be done? There is no greater profit or higher sales incentive there. You could argue that using the amounts they prescribe makes for more sales but shaking the bottles? I actually shake them all a few times before using them even though it doesn't say to.

Having to shake the bottle for 30 seconds and then the test vial for another 60 seconds is not an incentive to buy the kit. In fact, I bet it keeps some people from using it.

If it says that something needs to be shaken before use, in my experience, then it definitely needs to be done no matter what the product is.

kashbill
I try put 5ml to the small syringe then try put in the vial but it never be 5ml in , when I use 6.5 it does fill on the bar

Kasshan
I try put 5ml to the small syringe then try put in the vial but it never be 5ml in , when I use 6.5 it does fill on the bar

its 0.63mL not 6.3mL. you can round this number to 0.6mL and still get an accurate result.

hey -Mak- case in point about the metric system right here lol

Since you’ve stuck your career out there 20 times like you’re a world renowned neurosurgeon I’ll do the same, I’m an analytical scientest and was a surgical first assistant in vascular surgery for 3 years - I really hope that makes me seem really cool here on this fish forum.

While your math is very obviously correct I wouldn’t be so quick to conclude that API is ripping people off by using 5ml of water for testing purposes. It’s a 20 dollar test kit and works upwards of 100 times. The vast majority of casual hobbyists don’t even own them.

To think you’re the first person to realize the idea of a ratio on this forum is really insulting in and of itself and to be really honest your job as a pharmacy tech does effectively 0 to impress anyone. I know pharmacy techs who couldn’t pour pee out of a boot with instructions on the heel.

Gypsy13

Thank you.

why would the nitrate precipitate. calling it a "solution" is clearly a misnomer then and I guess the manufacturer mislabeled it. it can also be said from a marketing and sales aspect using more drops means people will consume the product faster and at different rates making the consumer buy more when not all test bottles are used up. using my reduced ratios all the chemicals would run out close to the same time and last much longer in the long run. now if you worked for API you would you want to sell more product? is it easier to follow to instructions verbatI'm or confuse your customers with math so that stretch their product out 5 to 10 times longer. I think you overestimate the average person's retention when it comes to HS chemistry and the metric system, etc. I tutor math and science and I am no longer shocked by (what I consider basic knowledge) what the average person has forgotten and must relearn.

Perhaps the company, API, knows it is selling these test kits to the “general public” and not chemistry, science, math majors or tutors. They therefore call the contents in their bottles “solutions” so as not to confuse the majority of the people buying their product. Your math is not at fault. Your lack of taking into consideration the average American fish keeper’s ability to determine consistency in their drops, is at fault. If a normal fallible human measures one large drop today and a small drop tomorrow, the test itself will be inconsistent. Therefore, after considering the human capacity for error, you are incorrect. Math perfect. Human nature not so much.

Since you’ve stuck your career out there 20 times like you’re a world renowned neurosurgeon I’ll do the same, I’m an analytical scientest and was a surgical first assistant in vascular surgery for 3 years - I really hope that makes me seem really cool here on this fish forum.

While your math is very obviously correct I wouldn’t be so quick to conclude that API is ripping people off by using 5ml of water for testing purposes. It’s a 20 dollar test kit and works upwards of 100 times. The vast majority of casual hobbyists don’t even own them.

To think you’re the first person to realize the idea of a ratio on this forum is really insulting in and of itself and to be really honest your job as a pharmacy tech does effectively 0 to impress anyone. I know pharmacy techs who couldn’t pour pee out of a boot with instructions on the heel.

Don’t be so high on yourself, you’re nowhere near as smart as you think you are and that’s hugely apparent by your cocky attitude. Smart people don’t go around telling everyone how smart they are, stupid people do.

Cool. I’m totally in awe now! Wait you’re a what? Oh never mind. Thought you said you were a neurosurgeon! Rofl!
Perfectly done sir.

TexasGuppy
I thought I was common knowledge that the nitrate test doesn't work without shaking to mix up the crystals? Having said that, I'm pretty sure a single drop would probably work fine afterwords.

Kasshan
*sigh* that is fine. but I know what I know. I certainly don't claim to know things I don't know.

it boils down to this. either consume the product under normal circumstances or choose to stretch a dollar using reduced ratios, how it became a debate is beyond me. but thank you for putting things in perspective. I was getting a little bit heated. I'm not above admitting I'm wrong, I probably shouldn't have appeared to be condescending, credibility is lost when one loses does that even when you are initially correct.

I apologize for my condescending tone and I let my emotions supersede my logic. I let this one get away from me

Regardless of opinions presented by myself and others, I still stand by test kit "hack"

consistency and precision in the scientific method is more important than accuracy. these test kits aren't exact , but they are close enough to allow wiggle room in the size of the drop.

Mick Frost
Smaller samples are less accurate, irregardless of how many drops of reagent are used.
When an environmentalist takes a soil sample, they use a tube about 3/4" in diameter and about 18" long, and they usually take a dozen of them. The test is engineered to test a specific sample size, and to be acceptably accurate with that sample size.
Scientifically, the test isn't even all that accurate when done according to the directions. A proper sample would include at least 6 separate draws of water, taken from different parts of the aquarium. It would then be read with a spectrometer instead of eyeballing the color against a mass-produced chart.
The test is what it is. It's accurate enough to keep billions of fish alive when used as directed, but it's still only 7th grade quality.