Ammonia can kill nitrifying bacteria?

terror

AC Members
May 23, 1999
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Manila, Philippines
Hi,

I've read some post that High ammonia can kill nitrifying bacteria?
Will high ammonia cause the cycling process to stop or restart?

thanks.
 
not something i've ever heard of, but i wouldn't think you could get high enough ammonia in the water to bother the bacteria unless you were pouring raw store ammonia onto your growth media
 
Ammonia levels around 5-6 ppm will begin to kill the beneficial bacteria.
 
If pH below 7, NH3 @ 5-6ppm wont kill fish but such high NH3 may disturb well establish nitrobacter/nitrospira inhibiting oxidation of NO2 to NO3 causing increase in NO2 which can be detrimental to fish unles controlled via pwc as needed. That is a reason for two step process of cycling.
 
Thanks. Reason for asking is because my tanks ammonia is at 8 , at least thats how high my ammonia tester goes, But i've been using ammolock,
tank is recyclling due to ph crash :( but i noticed that arowanas produce lots of ammonia . I've added a kilo of zeolite , but it doesn't affect the ammonia level :(
 
When you say pH crash, do you mean to low low pH.

When pH is low low, NH3 is virtually non toxic since they are in NH4+ (Ammonium)form. But by rasing pH close and higher than 7.4, such action will convert present NH4+ to toxic NH3. Make sure not to raise pH too much in presence of any NH4+/Nh3.
Simplest way to raise pH and lower NH4+/NH3 & NO2 is to perform small but frequent WC. If you could age the tap for day or two, it will assist in minimizing possible frequent WC shock with straight tap water.

I would be more concerned with any possible NO2 build up. And such can be controlled via small but frequent WC as necessary and with controlled feeding.
NO2 acts very similar to how Carbon Monoxide actc on human. Pretty toxic with acute and long term side effects/death.

It does not matter what kind of fish, tank will eventually establish enough BB to handle the bio load with time as long as pH doe not go too extreme for BB (and fish as well).

What is present pH/NH3/NO2?
 
When you say pH crash, do you mean to low low pH.

When pH is low low, NH3 is virtually non toxic since they are in NH4+ (Ammonium)form. But by rasing pH close and higher than 7.4, such action will convert present NH4+ to toxic NH3. Make sure not to raise pH too much in presence of any NH4+/Nh3.
Simplest way to raise pH and lower NH4+/NH3 & NO2 is to perform small but frequent WC. If you could age the tap for day or two, it will assist in minimizing possible frequent WC shock with straight tap water.

I would be more concerned with any possible NO2 build up. And such can be controlled via small but frequent WC as necessary and with controlled feeding.
NO2 acts very similar to how Carbon Monoxide actc on human. Pretty toxic with acute and long term side effects/death.

It does not matter what kind of fish, tank will eventually establish enough BB to handle the bio load with time as long as pH doe not go too extreme for BB (and fish as well).

What is present pH/NH3/NO2?
thanks. Yup my ph dropped to 5 a couple of days ago. It crashed after a 30% water change, I'm not sure what caused the crash. before water change the my ph was at 7, then i made a 30% water chaneg, my arowanas vomitted , since i have just finished feeding them when i did my water change. after they vomitted, I noticed they had a hard time breathing , I siphoned the food they regurgitated and made another 10% water change, I then tested water parameters, at that time the ph was still at 7, and ammonia at 0. the next day, since i was worried, I tested again and ammonia was at .25, ph was already at 5, then at night i tested and the ammonia has increased to 4.
it increases a lot in 1 day without my bio filtration :(
i've experienced this a few times before, and its really quite stressful trying to cycle with my arowanas in the tank :(

I'm currently using ammolock to try to neutralize the ammonia.
Also added some crushed corals, my ph is currently at 7 - 7.5
I'm trying to seed from my other sump tanks, but amonia just rises too quickly.
btw i'v ebeen doing daily 30% wc, but each time before wc, the ammonia will be at 8.
I've ordered some more zeolites, will be adding this to their sump to try to help with the ammonia.
 
thanks. Yup my ph dropped to 5 a couple of days ago. It crashed after a 30% water change, I'm not sure what caused the crash. before water change the my ph was at 7, then i made a 30% water chaneg, my arowanas vomitted , since i have just finished feeding them when i did my water change. after they vomitted, I noticed they had a hard time breathing , I siphoned the food they regurgitated and made another 10% water change, I then tested water parameters, at that time the ph was still at 7, and ammonia at 0. the next day, since i was worried, I tested again and ammonia was at .25, ph was already at 5, then at night i tested and the ammonia has increased to 4.
it increases a lot in 1 day without my bio filtration :(
i've experienced this a few times before, and its really quite stressful trying to cycle with my arowanas in the tank :(

I'm currently using ammolock to try to neutralize the ammonia.
Also added some crushed corals, my ph is currently at 7 - 7.5
I'm trying to seed from my other sump tanks, but amonia just rises too quickly.
btw i'v ebeen doing daily 30% wc, but each time before wc, the ammonia will be at 8.
I've ordered some more zeolites, will be adding this to their sump to try to help with the ammonia.

Loose the Crushed coral and Zeolite& Ammolock (waste of money). Use $ to invest in large containers, powerhead, and perhaps a heater (maybe) in order to age the tap..
You may be doing more harm than good by rasing your pH at this point. Until Ammonia is controlled, try to keep pH below 7.
If your tap is close to 7, just perform water changes without disturbing Bio medium.

What is your tap's pH/GH? Do you know if your tap has chloramine?

btw, what kind of of pH tester are you using which registers as low as 5? Perhaps you have digital pH monitor?
 
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I left a tank with 8ppm ammonia for months (5-6 months, something like that) as an experiment once (pH was 7.4) and the tank never showed signs of cycling. So that level will stop bacterial growth.

As Ceranthius stated, even lower levels have been shown to slow or stop bacterial growth.

In a fishless cycle you should be keeping your ammonia and nitrite below about 5ppm. With fish you should be keeping ammonia and nitrite around or below .25 ppm to prevent stressing or killing the fish.

A pH of 5 is definitely low enough to stall your cycle. Anything below 7 pH may be detrimental to your bacterial colonies.

If you raise your pH and you have fish present you need to be sure to add something like Prime, Amquel, Ammolock, etc., to detoxify the ammonia (it will still be available for your bacteria) because raising the pH will make the ammonia more toxic to your fish. You will also need to do several water changes daily to lower that ammonia level so you can cycle your tank. You may actually be better off doing a very large water change (replacing as much water as physically possible without leaving the fish dry) to get the ammonia controlled.

Loose the Crushed coral and Zeolite& Ammolock.
Why lose the crushed coral? The pH needs to be buffered anyway. If it keeps falling the pH and bacteria issues won't be resolved. The crushed coral shouldn't be detrimental to the cycle. The ammonia toxicity issues need to be taking care of by significantly lowering the ammonia and adding a detoxifier in the meantime.

Why lose the ammolock? Even while using it the ammonia will still be available for the bacteria to consume. I've used it during cycling many times and the tank will still cycle while using it. It also states this on the bottle.

I agree with losing the zeolite since the ammonia should be removed through water changes anyway.

If the ammonia is rising so fast then the tank is overloaded. Maybe consider cutting down on fish load. Only feed every few days and in small amounts. Clean the detritus out of your filters with tank water. Siphon any unconsumed food or poop out of the tank.

btw i'v ebeen doing daily 30% wc, but each time before wc, the ammonia will be at 8.
You need to get that ammonia down to at most .50ppm for the sake of your fish. You are not doing enough water changes to keep the ammonia low enough for your fish load. 30% daily is just not that much. If your ammonia is 8 and you do a 30% water change you're only bringing the ammonia down to about 5.6ppm. If you then immediately do another 30% water change you've brought it down to 3.92ppm. Another immediate 30% water change would equal about 2.744ppm. Get the picture? You're just not removing enough water to get that ammonia down significantly.
So you either need to do several water changes per day of that size, and/or do larger water changes. You should be able to safely do 50% water changes (though personally I'd do about 95% to get it down immediately if I had this issue since the fish are sitting in massive amounts of ammonia and other organics. Why worry about stressing them with a massive water change when they are already being stressed, possibly killed by the high ammonia?).

but i noticed that arowanas produce lots of ammonia
You may also be overfeeding. Aros will eat WAY more than they need to eat, not to mention a very fast growth rate. How many do you have, what size tank, how big are the fish? Your maintenance level just doesn't sound up to par with your fish load and feeding level. With one 22" arowana and one other fish in a 220g I was doing 50% water changes weekly to keep nitrates acceptable, and this was in a barebottom tank with good maintenance on the filters. What was your maintenance schedule before the crash?
 
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