Unusual Test Results

[Toby86]

I've been trying to cycle my tank ready for getting some guppies.
I'm using the NT Labs multi test kit.
And tetra safe start.
I've also been enlisting the help of chatgpt to interpret the results.
For close to a week it seemed like the cycling process was going well. Never saw any sign of ammonia. Nitrites were increasing. Nitrates also.
This morning I saw the first signs of nitrites going down and nitrates were still high. I tested again this evening, however and there seems to be no trace of ammonia, nitrites or nitrates.
I did multiple tests and used test tubes from a previous kit. All showing the same result.
I'm a little confused as I though nitrates were supposed to stick around a while after nitrites are gone.
While I did do a water change yesterday I've seen test results saying nitrates and nitrites were high after doing so. It was about a 40% change.
I have 2 questions.
1) the instructions on the kit imply that only reagent bottle 1 of the nitrate test is supposed to be shaken prior to testing. That's what I'd been doing though I shook both this evening as chatgpt told me to. Still 0ppm
2) Is it possible that my tank is cycled and is there a simple way to confirm before buying my fish?

 

[Uberhoust]

1) I don't use NT Labs but the API version only one bottle needs to be vigorously shaken, but I shake both bottles myself. I have proven to myself that if you don't shake them correctly you will get poor results with the amount of nitrate showing less than what's in the water. (confirmed by using a reference solution). I also had a Fluval test for Nitrate never worked no matter how much I shook the reagents.
2) Unlikely. It is the Ammonia and Nitrite that are the most toxic to the fish. If these are not down to zero your tank is not cycled. I would watch for cross contamination if you are not finding the results you expect.

Finally using a fishless cycle usually takes more time than a week. I don't use a fishless cycle but depend on plants mostly to keep the ammonia down but others in the group mention up to 6 weeks.

 

[MaloK]

I would think you tested at the perfect time to have no nitrite reading... But nitrate are still not apparent atm.

Continue on that trajectory, future tests should confirm my "theory"

This happens every time, you closely "follow' any fishless cycle in fact.

 

[Toby86]

It's been 24 hours since I got the unusual results and I've tested again. I made sure the tubes were thoroughly rinsed and dried. I've got the exact same result. No nitrites, no nitrates, no ammonia.

I've added a pinch of food to see if that changes anything.

I don't know if it makes a difference but I've been testing at the same time of day every day.

I really don't get what's happening.

Also, I don't know if it's relevant but the filter medium has been used in a tank with fish before. Though it's been dry for a couple of years.

All murkyness that my water had for a few days is gone. It's crystal clear ATM.

 

[Essjay]

I assume you added ammonia when you started the cycle; have you added any more ammonia since then?
This is how to do a fishless cycle

Cycling Your New Fresh Water Tank: Read This First!

Cycling Your First Fresh Water Tank What is Cycling and Why is it Important? Fish waste, and especially fish breathing, plus uneaten food and other organic matter breaking down in a tank all produce Ammonia. This can quickly become toxic to fish if it is allowed to build up to any measurable...

www.fishforums.net

Filter media which has been dry for a couple of years will have no bacteria left alive so the cycle is starting at the beginning.

The murkiness is common in new tanks. There are a few possible causes - dust from the substrate, bacterial bloom (not the bacteria we want to grow) etc.

 

[Toby86]

Update.
I tested plain tap water and it shows nitrates. Suggesting the testing reagents do work.

I assume you added ammonia when you started the cycle; have you added any more ammonia since then?
This is how to do a fishless cycle

Cycling Your New Fresh Water Tank: Read This First!

Cycling Your First Fresh Water Tank What is Cycling and Why is it Important? Fish waste, and especially fish breathing, plus uneaten food and other organic matter breaking down in a tank all produce Ammonia. This can quickly become toxic to fish if it is allowed to build up to any measurable...

www.fishforums.net

Filter media which has been dry for a couple of years will have no bacteria left alive so the cycle is starting at the beginning.

The murkiness is common in new tanks. There are a few possible causes - dust from the substrate, bacterial bloom (not the bacteria we want to grow) etc.

When I started the cycle I added tetra safe start and a pinch of food. For the next few days I added nothing. Then another pinch of food. Tiny pinches each time.

 

[Essjay]

Ah, that's why you are not seeing a proper progress. You need to add ammonia or ammonium chloride to feed the bacteria to cycle properly. Fish food has to decompose to produce ammonia before the cycle can start; it also has the disadvantage that you cannot know exactly how much ammonia is made so you cannot know if you have grown enough bacteria to support the fish when they are added. Using ammonia/ammonium chloride you know exactly how much is added and if you follow the instructions in my link you will have grown enough bacteria at the end of the cycle.


I would look on eBay or Amazon for Dr Tim's Ammonium Chloride and use that. The dose rate is given on the bottle as drops per gallon, that's US gallons and the calculator on here can convert water volume between litres and gallons (depending which unit you prefer)

Calculator

American members will suggest other sources of ammonium chloride but those are not available in the UK.

 

[Toby86]

Ah, that's why you are not seeing a proper progress. You need to add ammonia or ammonium chloride to feed the bacteria to cycle properly. Fish food has to decompose to produce ammonia before the cycle can start; it also has the disadvantage that you cannot know exactly how much ammonia is made so you cannot know if you have grown enough bacteria to support the fish when they are added. Using ammonia/ammonium chloride you know exactly how much is added and if you follow the instructions in my link you will have grown enough bacteria at the end of the cycle.


I would look on eBay or Amazon for Dr Tim's Ammonium Chloride and use that. The dose rate is given on the bottle as drops per gallon, that's US gallons and the calculator on here can convert water volume between litres and gallons (depending which unit you prefer)

Calculator

American members will suggest other sources of ammonium chloride but those are not available in the UK.

Ok. I'll give that a go. I'm still no closer to understanding why the nitrites and nitrates in my tank suddenly disappeared though.