Api Ammonia Reading Chart

[denismen]

Every time I test for ammonia it is between 0 - 0.25 but I based this on the colour chart with the API test kit. Every time I do a water check, always , the colour for ammonia readings never reaches a true yellow but is more between the yellow which is zero, and the pale greenish colour which is 0.25 and I always get this result.
Both my tanks give this reading every time but when I bring water to my local fish retailer they tested water several times and said it was zero, meaning safe, but when they showed me the water it was the same colour I always get which is not a true yellow.
Does anyone else use these water tests and do you get a true yellow reading from them.
My male guppy has shimmies and my female platy is jerking/twitching but not swimming in a shimmying way like the guppy, and I was tiold she may have shimmies also.
2 days ago: Ammonia = 0 - 0.25, Nitrite = 0, Nitrate = 80, PH = 8...changed 30% water and added "Disease Clear"
1 day ago:  Ammonia = 0 = 0.25, Nitrite = 0, Nitrate = 40, PH = 7.8 - 8....changed 30% water
Will test water again in about 7 hours and see if I need to change water again.
Am I changing enough water also?
 

 

[goldfinger]

I have the same issues if I think its more yellow than Green is safe! You will find the colour goes quite green but what helps if I look through the tube in light its more yellow its safe if I look through the tube in direct light and see its clearly green then you have trace of ammonia its hard as some test cards colours fade or when you do drops of test liquid sometimes bottle two has more air bubbles than liquid soultion making the result hard to see. After a big shake of the bottles I let it settle so air bubbles go and I get true drops hitting the water. Hope it helps I've been there but after a million tests I make a good call to say its safe plus Nitrates are zero which means Ammonia would be the same if I have strong Nitrites garanteed I'll have Ammonia trace.  Logic dictates one follows another?

 

[Lunar Jetman]

I have heard that this is common with this test kit, that you get false readings at low levels. Logically if you have 0.25 Ammonia and you change 50% water you should then have 0.125 Ammonia.
 
I'd do say 50% if you're worried about the levels and see what the test kit shows afterwards.

 

[TwoTankAmin]

The odds are good the reading is off. The simplest way to see this is from the nitrite test. We know that the ammonia eating bacteria produce nitrite. We also know the nitrite eating bacteria reproduce more slowly than the ammonia ones. So think about the cycling process for a minute.
 
You start out with neither any meaningful bacteria or ammonia in a tank. Then ammonia gets added, either by dosing or adding fish. And then we see ammonia but no nitrite. The ammonia begins to drop and the nitrite begins to rise. The ammonia drops but nitrite continues to rise before turning down and dropping to 0. What this tells us is that the ammonia eaters build up until they are handling all the ammonia in the tank. but the nitrite eaters lag behind and must catch up to the ammonia ones.
 
So, if one has a real ammonia reading in a tank it means there are not enough bacteri yet to convert all the ammonia to nitrite. And this also means there are not enough nitrite eaters to handle everything the ammonia eater will be making. Think of it this way. You get a tank fully cycled to process 1 ppm of ammonia and the nitrite that ammonia will produce. Now increase the ammonia to 2 ppm. The ammonia eaters will multiply to handle that ammonia, and this means they will be making more nitrite. But the nitrite eaters are laggards, So when the increased nitrite is created from the ammonia, the nitrite eaters can not yet handle it and there will be a nitrite reading.
 
Now apply this to that pesky .25 ppm reading. You see it every day but you never see a nitrite reading. If that ammonia reading is correct it means there is more ammonia in the tank than the ammonia eaters can process. And that means the ammonia eaters should increase in number to handle the ammonia and when they do, it means there will be more nitrite than the nitrite eaters can handle until they catch up.
 
But the nitrite never reads above 0. This means there are only two possibilities (assuming test kits are not outdated and testing is being done properly). One is that the ammonia reading is wrong, the other is the nitrite reading is wrong. Given the nature of the two tests, I will opt for a false ammonia reading over a false nitrite one almost any day.
 
So what we need to do in cases of those pesky low level ammonia readings that don't seem to go away, is to assess things logically. If its a new tank just starting a cycle that is not the same thing as a tank where ammonia spikes up and dropped, then nitrite went up and dropped etc. If the .25 ammonia and 0 nitrite readings are just for one day, it is not the same thing as seeing this day after day for some time.
 
We need to pause and ask ourselves what the source of that .25 ppm of ammonia is. Exactly what would cause a constant .25 ppm reading of ammonia day after day? Such consistency itself should tell us something is not quite right. If you were challenged to create a tank that could be tested any time of day and day after day at the same ammonia level, I highly doubt you, (or I) could do this. There should be some fluctuation. The ammonia eating bacteria can double in as little as about 8 hours, all they need to increase their numbers is sufficient food (ammonia etc,). So why wont that stubborn .25 ppm reading go down? For my money, the answer is that there really is not .25 ppm of ammonia present, the ammonia test kit reading is not right.
 
I have found that the inexpensive aquarium type kits tend to become most unreliable at extremes- that is very low or very high levels. therefore, it is important to consider results in light of the situation.

 

[snazy]

I don't go by the colour on the chart because there isn't much difference between 0-0.25.  If there's unsafe level of ammonia, the surface of the test tube liquid goes greenish, where the 0 is definately yellowish/beige. That's the only difference I've found out between 0-ish and 0.25ppm.
And consider there's always ammonia in a fish tank, just way below a 0.25 level but still above 0, possibly something of the sort 0.05 or similar.

 

[denismen]

Thanks to everyone for those informative replies.
It appears that most people seem to have similar problems figuring out the right ammonia readings.
I will test the water in a couple of hours and possibly change 50% water to see if it helps.

 

[daizeUK]

The colour for zero ammonia on the test card is far too orangey, I've never seen my results go that colour.
I take a zero reading if the water looks yellowish compared to the 0.25 colour on the card.

 

[goldfinger]

Daize can you post a picture of your card its supposed to be yellow! I've never heard an API being described orangey? Weird did you leave it in direct sunlight as this can discolour the card over time?

 

[daizeUK]

Yeah sure, it's not the best picture but here:

 
The test card has orange pixels overlaid on the yellow which gives it a misleading colour.
 
The test tube on the left is what I consider a zero reading... it is distinctly yellow compared with the 0.25ppm colour... but never amber like the 0 ppm on my test card.
 
I often look at the tube in different lights, facing away from the window, facing towards the window and at different angles before I decide what reading to take.  It's especially hard to read on sunny days when there tends to be more shadows and reflections (even when not in direct sunlight itself).