Freshwater Fish less Cycle

Last night the ammonia dropped to 0.25 ppm so I re dosed it back to 1.0 ppm this morning when I tested the water it shows the nitrites are consuming pretty quickly, The thing is the nitrites are not lowering as you can see they continue to increase. Weird thing is if I wait 24 hours the ammonia consumes and goes down and when I test the nitrites shaking the bottle for a few minutes it shows 0.25 ppm but if I shake it any longer it shows the nitrites higher.

With the API nitrite test, you add the drops from the bottle to the tube, shake the tube to mix the drops in thoroughly, then let the tube stand for 5 minutes and compare to colour to the chart. It should always be compared to the chart after exactly 5 minutes, and the same for the ammonia and nitrate tester. None of them need to be shaken after the start of the 5 minutes. The only slight difference is with nitrate as the tube should be shaken for 1 minute before starting the 5 minute stand.
What is the colour in the nitrite tube exactly 5 minutes after adding the reagent?

There is another alternative. Get a lot more plants, particularly floating plants. Once you have them, empty all the water out of the tank (to get rid of all the nitrite) and refill, planting any rooting plants at the same time. Then add the floating plants. Wait a few days to make sure the plants are happy and get some fish, but not the entire planned stocking just yet. And test every day till you are sure there is no ammonia or nitrite.
The filter bacteria can already cope with ammonia; it's just nitrite that's lagging behind. Plants will also use use ammonia, and they will use it before the bacteria, so there may well be no nitrite appearing.

essjay said:

With the API nitrite test, you add the drops from the bottle to the tube, shake the tube to mix the drops in thoroughly, then let the tube stand for 5 minutes and compare to colour to the chart. It should always be compared to the chart after exactly 5 minutes, and the same for the ammonia and nitrate tester. None of them need to be shaken after the start of the 5 minutes. The only slight difference is with nitrate as the tube should be shaken for 1 minute before starting the 5 minute stand.
What is the colour in the nitrite tube exactly 5 minutes after adding the reagent?

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I tested the nitrites again they look to be 1.0 ppm

essjay said:

There is another alternative. Get a lot more plants, particularly floating plants. Once you have them, empty all the water out of the tank (to get rid of all the nitrite) and refill, planting any rooting plants at the same time. Then add the floating plants. Wait a few days to make sure the plants are happy and get some fish, but not the entire planned stocking just yet. And test every day till you are sure there is no ammonia or nitrite.
The filter bacteria can already cope with ammonia; it's just nitrite that's lagging behind. Plants will also use use ammonia, and they will use it before the bacteria, so there may well be no nitrite appearing.

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I am thinking about starting the entire tank over again. Hate to waste all this time but don't know really what else to do. Other tanks I have in the home have never had these kind of results even though the other tanks have fake decorations and no driftwood and no plants of any kind they still fishless cycled with no issues. Maybe I should just clean the tank remove all the old water and just leave the filter like it is without cleaning it dose some prime and add a few fish and go from there.

The nitrites have already been going sky high anyways rather then going down much so I have already had to do several 50% water changes to keep the nitrites from stalling the cycle from the get go. With prior tanks fishless cycling I never had to do one water change till the cycle had completed this one has not been the case. Fishless cycling in this tank has been a nightmare.

Here are the readings tonight. They look to be changing. Wonder if I should wait to re dose ammonia till I see if nitrites hit zero are re dose the ammonia again?

I am still fish less cycling a 20 gallon long but wanted to ask in advance why the tank is still fish less cycling in regards to chemicals being added or possible waiting. The gH I have in the tank is reading 3 and the kH in the tank is reading 6. With these two I am holding my pH at about 7.2 ppm now. I have read information that suggest to have gH of at least 3 and the kH of at least 6 for most tropical fish. Since I am wanting to keep a few mystery snails as well in the tank down the road what is the recommended gH & kH that other fish owners have kept there own snails in which worked good for them and for the fish?

Is the gH & kH something I should go ahead and pin point during a fish less cycle now as for dosing or wait after the tank is cycled? The stocking I have in mind will be two mystery snails, Six Panda Cory and Eight Harlequin Rasbora. Also if it is advised to increase the gH & kH now would all other fish listed be suitable for the same gH & Kh increase as well? I am aware that snails will eat a lot of veggies but is that enough or good enough or should I also look for a specific gH & kH number on both as well.

The only reason you need to know your GH is so that you can choose fish which need that GH. With your soft water you need to keep fish that like soft water.
The only reason you need to know your KH is so you know that you must do large regular water changes - which you should do anyway once you have fish regardless of KH - so that the pH does not undergo large changes. Fish do not need a KH of at least 6 dH. Fish for themselves do not require any KH, it's only use for them is to keep the pH stable. My KH is 3 and my fish have no trouble with that - I also do weekly 50% water changes.
Your fish wish list is fine at your GH and KH.

The problem might be the snails. With low hardness, particularly if that goes with low pH, snails will suffer from shell erosion. I am lucky that although my water is softish, it is not too low, and my pH is 7.5. But I think that people who do have soft water and pH below 7 use a source of calcium such as cuttlefish bone, a small piece of coral or a small shell to provide the calcium that snails need.
Hopefully someone who has low GH will be able to help you with them - maybe make a new thread in the "shrimps and other invertebrates" section to ask.


The only reason that low KH is a problem during fishless cycling is because cycling makes lots of acid and you don't do water changes. The acidic things use up the small amount of KH and no water changes means the acidic things aren't removed and the KH isn't replenished. This results in the pH dropping very low which stops the bacteria multiplying so the cycle stalls.




I still think your best approach would be to get a lot more plants, and floating plants in particular. Drain the tank to remove any baking soda you've added and to get the nitrite reading to zero, then plant the plants as you refill the tank. Wait a few days to make sure the plants don't start to die, then go and get the harlequins. Monitor the ammonia and nitrite levels every day and do a water change if either shows up. Once they've been at zero for a couple of weeks, get the cories and monitor the levels every day till you are sure they are staying at zero.
Don't add any ammonia for the few days between draining the tank and getting the harlies. The bacteria you have grown won't starve, and your plants won't be happy if you add ammonia. Fish waste adds ammonia in minute amounts throughout the day. When we add ammonia to the tank, we add the amount of ammonia in one go that the fish will make over the course of a whole day, and plants don't like that.

Checked the water this morning, Ammonia was at zero so I re dosed the ammonia some. Should I do a small water change or does the nitrites look to be okay?

The fishless cycling method says that you only add the snack dose of ammonia when you get zero ammonia, and two days later another zero ammonia. You must wait for two zero ammonias two days apart before adding more ammonia or you'll get too much nitrite made. The colour in the nitrite tube looks to be at 5 ppm in the photo, so it could be 5 or anything above 5.
How much ammonia are you adding? You shouldn't be adding more than the amount that gives a reading of 1 ppm or your plants will suffer.

I would stop adding ammonia and wait a week. This will not starve the ammonia eaters and it will give the nitrite eaters chance to grow.

essjay said:

The fishless cycling method says that you only add the snack dose of ammonia when you get zero ammonia, and two days later another zero ammonia. You must wait for two zero ammonias two days apart before adding more ammonia or you'll get too much nitrite made. The colour in the nitrite tube looks to be at 5 ppm in the photo, so it could be 5 or anything above 5.
How much ammonia are you adding? You shouldn't be adding more than the amount that gives a reading of 1 ppm or your plants will suffer.

I would stop adding ammonia and wait a week. This will not starve the ammonia eaters and it will give the nitrite eaters chance to grow.

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I have been adding ammonia when it drops to zero, Re dosing 1.0 ppm only. The nitrites are consuming the ammonia at 1.0 ppm pretty quickly within a two day period. During this process my nitrites are always high unless I do a water change then of course it will drop same as the nitrates. I hear what your saying but wanted to explain this as well. I went ahead and did a 50% water change to lower the nitrites and did not re dose the ammonia even though it shows to be zero. Here are the readings after the water change. Should I wait till the nitrites also hit zero before I re dose the ammonia again?

It isn't nitrites that consume ammonia, it's bacteria that use ammonia as food, and they 'poop' nitrite. A second type of bacteria uses nitrite as food, and they 'poop' nitrate. You are at the stage where you have enough ammonia eating bacteria to eat all the ammonia you add, but you don't have enough nitrite eating bacteria to eat all the nitrite that the ammonia eaters make. And too much nitrite stops the nitrite eating bacteria from multiplying so the cycle stalls.
The problem is that the bacteria turn 1 ppm ammonia into 2.7 ppm nitrite. It just takes 2 ppm ammonia to push the nitrite level higher than the tester can read. 6 ppm ammonia is turned into enough nitrite to stall the cycle.



Your latest photo shows nitrite lower than the previous one. Don't add any more ammonia, wait till Friday and test again. If ammonia is zero again on Friday, add 1 ppm ammonia and test on Sunday and again on Tuesday.
Tell us next Tuesday what your ammonia and nitrite readings were on Sunday and Tuesday and we'll take the next step based on those readings. Don't add any ammonia after Friday until we see your readings on Tuesday.

essjay said:

It isn't nitrites that consume ammonia, it's bacteria that use ammonia as food, and they 'poop' nitrite. A second type of bacteria uses nitrite as food, and they 'poop' nitrate. You are at the stage where you have enough ammonia eating bacteria to eat all the ammonia you add, but you don't have enough nitrite eating bacteria to eat all the nitrite that the ammonia eaters make. And too much nitrite stops the nitrite eating bacteria from multiplying so the cycle stalls.
The problem is that the bacteria turn 1 ppm ammonia into 2.7 ppm nitrite. It just takes 2 ppm ammonia to push the nitrite level higher than the tester can read. 6 ppm ammonia is turned into enough nitrite to stall the cycle.



Your latest photo shows nitrite lower than the previous one. Don't add any more ammonia, wait till Friday and test again. If ammonia is zero again on Friday, add 1 ppm ammonia and test on Sunday and again on Tuesday.
Tell us next Tuesday what your ammonia and nitrite readings were on Sunday and Tuesday and we'll take the next step based on those readings. Don't add any ammonia after Friday until we see your readings on Tuesday.

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I just tested the water again after that 50% water change waited like what a hour to test, Unless I am blind it is showing the tank cycled? I also checked the Kh & Gh they are both reading 3 each from the tanks water.

Well I did not want anymore Neon's so picked up 6 Zebra Danios today. Will monitor the water and fish activity over the next couple of weeks. Hopefully there wont be any issues. Thank You

Update tank cycled !!!

I need your advice once again on this setup.

Just so I do not over stock the tank would a stock of the following be to much for this tank or is it under stock? More plants on the way to include water sprite and java moss and more amazon swords. I presently have my tank water at these readings and holding. Increased the gH so the snails will have a good solid calcium start for the shells. How does all this look? Thank You

pH 7.2 ppm
Ammonia 0 ppm
Nitrites 0 ppm
Nitrates 10 ppm
kH 6 gH 8

6 - Zebra Danios ( Have )
6 - Panda Cory ( Want )
5 - Mystery Snails ( Want )
5 - Ghost Shrimp ( Want )