Cycling issue - nitrite keeps building up

BilboB

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I'm trying to cycle my 55g tank with TurboStart 900 and Dr. Tim's ammonium chloride. Every time I add the ammonium, it's rapidly converted to nitrite but the nitrite is poorly converted to nitrate... so the nitrite builds up, and it takes 2 40% water changes and waiting a few days to reduce the level to near-zero. This suggests that the ratio of ammonium-utilizing bacteria to nitrite-utilizing bacteria is too high - but why?

Also, from now on, should I add less ammonium chloride each time? Maybe I should start with 1 drop per gallon instead of 4 drops so that the nitrite doesn't reach inhibitory levels. Then, after the nitrite level drops to near-zero, try 2 drops per gallon? The instructions say the tank is cycled when, the day after adding 4 drops per gallon, the ammonia and nitrite levels are near-zero. Do I really need to get to 4 drops per gallon? It's been almost 3 weeks already and I'm eager to add my fish.
 

Dan_P

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I'm trying to cycle my 55g tank with TurboStart 900 and Dr. Tim's ammonium chloride. Every time I add the ammonium, it's rapidly converted to nitrite but the nitrite is poorly converted to nitrate... so the nitrite builds up, and it takes 2 40% water changes and waiting a few days to reduce the level to near-zero. This suggests that the ratio of ammonium-utilizing bacteria to nitrite-utilizing bacteria is too high - but why?

Also, from now on, should I add less ammonium chloride each time? Maybe I should start with 1 drop per gallon instead of 4 drops so that the nitrite doesn't reach inhibitory levels. Then, after the nitrite level drops to near-zero, try 2 drops per gallon? The instructions say the tank is cycled when, the day after adding 4 drops per gallon, the ammonia and nitrite levels are near-zero. Do I really need to get to 4 drops per gallon? It's been almost 3 weeks already and I'm eager to add my fish.
In saltwater aquaria, it takes a time for the nitrite to disappear, but it turns out that nitrite is not so toxic. Many folks forge ahead before nitrite disappears.
 

Fish Fan

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Sounds like you're cycled to me 🙂

Yes, the nitrite oxidizing bacteria do take longer to establish, but as mentioned above, nitrite is non-toxic in marine tanks, so you can safely ignore it.

If your tank is processing the ammonia additions quickly (in about 24 hours), then you're good to go. There's no reason to keep adding ammonia.

Have you tested for nitrate yet?
 

Lasse

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Stop adding ammonia - the ammonia oxidation works well - you do not need anymore. It taks time for the nitrite oxidizers to build up their biomass. If you have started total dry - you may need to add a little PO4 - sometimes when it stall at NO2 - it will help because the Nitrite oxidizing bacteria also need PO4 in order to grow. If you slowly introduce a fish - just feed him/her very sparsely in the beginning. as mentioned before - NO2 is not especially toxic in saltwater. You can get some tips here

Sincerely Lasse
 

dloberry

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Agree with all comments. Takes time for the process. Eventually nitrite will disappear, but stop adding ammonia. You can begin slowly adding livestock if you want.
 

BeanAnimal

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Where is this “keep dumping ammonia and bottled bacteria until nitrite is zero” advice coming from (honestly)? It certainly feels like it has become the prevailing bad advice and we are seeing it almost daily.
 
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BilboB

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Oh, that's great news... I'll start adding my fish.

I was following Dr. Tim's protocol, which calls for repeated ammonium dosing until both ammonia and nitrite are removed within 24 hours:

 

BeanAnimal

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The Irony in Dr. Tim’s instruction about confusion is palpable. They are creating confusion in the name of hawking more product for profit.
 

Lasse

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Oh, that's great news... I'll start adding my fish.
You won't kill your fish if you start now, but - in my opinion - it is very wise to introduce fish in stages and over time - above all, it is the amount of food you give that is important. More food - more ammonium - more nitrite (if the second step doesn't work) - more nitrate. Start with a well-fed and hardy fish and take it easy with the feeding.

Sincerely Lasse
 

BigDom75

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Where is this “keep dumping ammonia and bottled bacteria until nitrite is zero” advice coming from (honestly)? It certainly feels like it has become the prevailing bad advice and we are seeing it almost daily.
I am a new reefer and just found this forum. The bad advice is coming from AI. Claude is telling me to keep redosing ammonia as it gets to 0 because my nitrites haven't dropped yet. AI is also very against adding livestock if nitrites persist which contradicts most of the posts I am seeing here.
 

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I am a new reefer and just found this forum. The bad advice is coming from AI. Claude is telling me to keep redosing ammonia as it gets to 0 because my nitrites haven't dropped yet.
Stop dosing ammonia - the first process - ammonia to nitrite works well and if you keep dosing ammonia - nitrite will rise much more. And learn - do not trust AI when you handling live support systems.

Sincerely Lasse
 

Randy Holmes-Farley

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I am a new reefer and just found this forum. The bad advice is coming from AI. Claude is telling me to keep redosing ammonia as it gets to 0 because my nitrites haven't dropped yet. AI is also very against adding livestock if nitrites persist which contradicts most of the posts I am seeing here.

That redosing of ammonia doesn’t make sense even in freshwater where nitrite is a concern.
 

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