High Nitrate Or Water Change Stalled My Cycle?

[r.d.bid]

I had read here on these forums that high nitrate levels may stall a cycle and a water change to lower them would be a good idea.
Two days ago, I did a 50% water change to bring down levels of nitrate since they were off the charts. Things in the tank were progressing just fine before the water change, but I thought it prudent and I certainly didn't want my cycle to take any longer than necessary. And now, even after changing the water, levels of nitrates are still off the chart.

Now the next day I noticed that ammonia was being processed, but at a much slower rate and today it seems as if ammonia is not being processed at all since the levels are still at the same place they were the day before.
Has my cycle stalled now due to high nitrate levels or is it something else?
Was it the water change that caused the cycle to stop?
Reason I think this, is that I have a 20 gal. tank that I am doing a fish-in cycle and it's been over 50 days and not a single sign of ammonia being processed. But I change the water in that tank every day to keep my fish from dying.

I dechlorinate any water I put in the tanks with Tetra Aquasafe Plus. This stuff allegedly removes heavy metals, chlorine and chloramines from the tap water.
Is it possible that it's not working or that I'm doing something wrong?
I fill buckets of tap water and add the proper amount of the dechlorinator in and mix well. I also let it stand for a couple of minutes before adding the water to the tank.

Please help me out here. What are your thoughts on this?

Is it the high level of nitrates that have stalled the cycle in my 50 gal. tank or was it the water change?
I'm leaning towards it being the fault of the water change since I can't get a cycle started in my other tank where I change the water every day. Is the dechlorinator not working? Maybe chlorine levels are so high in my tap water that it isn't all being removed by the prescribed amount of dechlorinator?

I'm really frustrated as I have one fish tank that had its cycle stop and another fish tank that wont begin to cycle and it has been over 50 days.
I really want to throw all my tanks in the trash and forget about ever keeping fish as this process has been so infuriating.

 

[snazy]

It's not the ammount of nitrAtes that stall a cycle. The process that converts ammonia to nitrIte is an acidifying process itself that can eventually crash the Ph in a tank and hence, stall the cycle as they say.

If you are dosing dechlorinator per the recommended level to remove chlorines and chloramines presuming there's no ammonia in your tap water, and if you match the temperature to the one of the tank, then it is highly unlikely this has something to do with the slow cycle.

Also, since you say the nitrAtes are high(I am presuming you are not talking about nitrItes), then the cycle has been going on for a while but has now stopped, otherwise you will have no nitrAtes(unless your tap water has high nitrAtes) On a side note, nitrAte of up to 20ppm thereabouts are ok for fish on constant basis and once a week water change should deal with any excessive ammount produced. Also keep in mind that 50% water change will remove only 50% of nitrAtes, or watever else is in the water, like the toxic ammonia and nitrItes. So if you want to remove more than that, then do a larger water change.

First of all, I would test the Ph of the water, test the tap water for ammonia, nitrItes and nitrAtes as well. Also, make sure the cycling tanks have enough oxygen(filter disturbing the surface at least). What's the temperature you are keeping your tanks at?
Also, since nitrAtes are building up and ammonia is also present, there is another alternative that your filters are not good enough for the size of the tanks.

 

[Electric Warrior]

Yeah, what is the PH level in your tank? As mentioned above, my cycle also stalled and the ammonia started to process slower as well, because my PH kept crashing to 6 or below.. I also had a high nitrAte reading, like deep red colour, which I believe often goes hand in hand with having a PH crash. I had do two or three 90% water changes to get the PH level back up and the nitrate level to lower in order to finish my cycle. My PH still continued to drop into the low 6's during my cycle, so I had to add baking soda a few times to bring it back to about 7.4 to allow the cycle to finish.

 

[r.d.bid]

Thanks for the reply Snazy and Electric

My baseline tap water readings are: 8.0pH, 0 Ammonia, 0 Nitrites, 0 Nitrates. 78-82 degrees F.
My tank is kept at 87F.
I did fill the tank up to a higher level so there is less surface agitation over the past two days. Could that be the reason?

The cycle has been going great. NitrItes are off the chart and NitrAtes are off the chart too. Ammonia was being processed at about 1.0 to 1.5ppm per 24 hour period.
I test this tank every day and have watched them go from zero to the levels that they are at now.
8.2 ph, .75 ammonia, off chart (+5.0ppm) nitrite, off chart (+160ppm) nitrate, 87 deg. F.

 

[snazy]

Thanks for the reply Snazy and Electric

My baseline tap water readings are: 8.0pH, 0 Ammonia, 0 Nitrites, 0 Nitrates. 78-82 degrees F.
My tank is kept at 87F.
I did fill the tank up to a higher level so there is less surface agitation over the past two days. Could that be the reason?

The cycle has been going great. NitrItes are off the chart and NitrAtes are off the chart too. Ammonia was being processed at about 1.0 to 1.5ppm per 24 hour period.
I test this tank every day and have watched them go from zero to the levels that they are at now.
8.2 ph, .75 ammonia, off chart (+5.0ppm) nitrite, off chart (+160ppm) nitrate, 87 deg. F.

Yes, bring the water level down or put the filter output up for the surface to move for more oxygen.
Second reason I didn't mention above for stalled cycle is high nitrItes but you didn't say you had any. There are enough researches saying that high ammounts inhibit both ammonia and nitrIte eating bacteria. You need to do a 90% water change, keeping enough water for the fish to stay upright. Make sure it's temperature matched and dechlorinated not to cause too much stress to them. If there's no fish in the tank, then even easier. Even during a cycle you can't have these high levels.
How much ammonia are you dosing?

 

[r.d.bid]

So high nitrIte levels will stall the cycle? Ok, I will do a 90% water change then. Also this is a fishless cycle.

Starting out the cycle i was dosing ammonia to 4ppm but I have reduced that to 2-3ppm since I was getting high levels of nitrItes.

 

[snazy]

So high nitrIte levels will stall the cycle? Ok, I will do a 90% water change then. Also this is a fishless cycle.

Starting out the cycle i was dosing ammonia to 4ppm but I have reduced that to 2-3ppm since I was getting high levels of nitrItes.

Yeah, if nitrItes can't even be measured on the test(over 5ppm), do a large water change to keep them below that level. It's hard in a fishless cycle to keep them below 0.25, but the lower the better. In a fish in cycle, aim for 0 nitrItes because they are more toxic to fish than ammonia at the same level.

 

[r.d.bid]

Will these high levels have killed off the good bacterias or just put them to sleep?

 

[snazy]

Just on a side note, but let's say that in a fishless cycle, out of the 50 days cycle you dosed ammonia for only 20 days up to 4ppm each time without water changes as normally most fishless cylcing articles don't mention you need one till it's all cycled. Considering that ammonia to nitrIte ratio is about 2.7, then that makes 217 ppm nitrItes accumulated in your tank or slightly lower if there's any bacteria grown to eat it. And of course you would think it's a bit high, but you'll never realise how high because most home test show only up to 5ppm!!! In a normal cycled tank with fish in, this will never happen and the bacteria does not tolerate these levels. It can lead to wrong type of bacteria growing and eventual spikes once you add the fish. Not to mention that 20 days of 4ppm ammonia leads to nearly 300ppm nitrAtes!!! and lots of acids added, and if people use tap water low on buffering capacity, then the Ph issue we mentioned above happens.

Will these high levels have killed off the good bacterias or just put them to sleep?

Put them to sleep more likely. It doesn't die that easy.

 

[r.d.bid]

Just on a side note, but let's say that in a fishless cycle, out of the 50 days cycle you dosed ammonia for only 20 days up to 4ppm each time without water changes as normally most fishless cylcing articles don't mention you need one till it's all cycled. Considering that ammonia to nitrIte ratio is about 2.7, then that makes 217 ppm nitrItes accumulated in your tank or slightly lower if there's any bacteria grown to eat it. And of course you would think it's a bit high, but you'll never realise how high because most home test show only up to 5ppm!!! In a normal cycled tank with fish in, this will never happen and the bacteria does not tolerate these levels. It can lead to wrong type of bacteria growing and eventual spikes once you add the fish. Not to mention that 20 days of 4ppm ammonia leads to nearly 300ppm nitrAtes!!! and lots of acids added, and if people use tap water low on buffering capacity, then the Ph issue we mentioned above happens.

That makes perfect sense.
Thanks so much for your help Snazy, it's really appreciated. I'm doing a water change right now.
I really hope this gets my cycle back on track cus I have had a very difficult time getting a cycle started in my other (very first) tank. It just doesn't want to start cycling so I paniced when the tank that is cycling stalled out on me.

 

[snazy]

No problem. Let us know how it goes but a large water change to remove all should do the trick. If you see anything above 5ppm for nitrItes, large water change again. You shouldn't be far off the finish stage honestly.

 

[r.d.bid]

Unfortunately my cycle never recovered. I'm not processing any ammonia or nitrites now.

I'm convinced that it's the dechlorinator that I'm using. I don't think it works or doesn't neutralize chlorine thoroughly enough or quickly enough. It would also explain why I can't get a cycle started in my other tank. I mean, 50+ days of daily water changes and not a start to a cycle.