Cycle Slowed Down After Water Change

I'm nearly at the end of my fishless cycle and I think I messed up... I did a big water change two days ago because my tank FINALLY cycled completely and nitrates were off the charts, and now my tank is cycling ammonia at a rate of 1ppm in 24 hours instead of 2ppm
However my nitrites are still at zero and my nitrates have gone up to 10 or 20, so it seems like my ammonia bacteria are the only ones that have gone down..I guess I'll add another 1ppm of ammonia for now
Is there a way to speed things up a little? I just want to get this over with! ugh

I'm guessing it happened because I might have slightly overdosed on Prime? I also changed like 90% of the water but I made sure the filter stayed wet and the gravel didnt dry out
That's what I get for not double checking what I was doing... I've been cycling for almost three months now

 

I'm nearly at the end of my fishless cycle and I think I messed up... I did a big water change two days ago because my tank FINALLY cycled completely and nitrates were off the charts, and now my tank is cycling ammonia at a rate of 1ppm in 24 hours instead of 2ppm
However my nitrites are still at zero and my nitrates have gone up to 10 or 20, so it seems like my ammonia bacteria are the only ones that have gone down..I guess I'll add another 1ppm of ammonia for now
Is there a way to speed things up a little? I just want to get this over with! ugh

I'm guessing it happened because I might have slightly overdosed on Prime? I also changed like 90% of the water but I made sure the filter stayed wet and the gravel didnt dry out
That's what I get for not double checking what I was doing... I've been cycling for almost three months now

Keeping the filter wet helps, but depending on the filter type you have, the oxygen available to the Nitrosomas might have been restricted. As long as you're getting ammonia breakdown at all is a good sign. The only thing you can do to speed things up is what you're already doing...feed them some ammonia. Nitrosomas don't just grow before Nitrobacter, they grow faster. Even in the clearest of tanks, there are free floating Nitrosomas in the water, and of course on the substrate and aquarium sides and decorations that all help with the overall filtration. 90 percent of water change is pretty radical. Try doing 25 percent per day over a 4 day period the next time nitrates get too high instead of all at once. I change 25 percent of my 55 gallon tank and I only do it because I like vacuuming the bottom often because I like using an undergravel filter along with my canister filter. I never have problems with nitrates because of houseplant cuttings. The front of my tank is great. But my nitrate eating factory behind the tank looks messy. But it does the job and is hidden by the background on the tank. Here's a pic of the back of my tank.

 

Keeping the filter wet helps, but depending on the filter type you have, the oxygen available to the Nitrosomas might have been restricted. As long as you're getting ammonia breakdown at all is a good sign. The only thing you can do to speed things up is what you're already doing...feed them some ammonia. Nitrosomas don't just grow before Nitrobacter, they grow faster. Even in the clearest of tanks, there are free floating Nitrosomas in the water, and of course on the substrate and aquarium sides and decorations that all help with the overall filtration. 90 percent of water change is pretty radical. Try doing 25 percent per day over a 4 day period the next time nitrates get too high instead of all at once. I change 25 percent of my 55 gallon tank and I only do it because I like vacuuming the bottom often because I like using an undergravel filter along with my canister filter. I never have problems with nitrates because of houseplant cuttings. The front of my tank is great. But my nitrate eating factory behind the tank looks messy. But it does the job and is hidden by the background on the tank. Here's a pic of the back of my tank.View attachment 437127

Well at least they should recover quickly then! I love that idea with the houseplants too, I'm going to be putting duckweed in my tank because I've heard that's a good nitrate suck
Thanks!!

 

Well at least they should recover quickly then! I love that idea with the houseplants too, I'm going to be putting duckweed in my tank because I've heard that's a good nitrate suck
Thanks!!

Duckweed is one of my favorite pond plants because the koi and goldfish love them. But in an aquarium, you'll be throwing out net fulls at a time. They multiply so fast that nearly all of your light will be blocked. They can also lower the oxygen exchange at the water surface hindering it's flow. Like I said, I love it for ponds, but you may want to consider some other options for your aquarium.

 

I am not sure I understand the OP. If you had nitrites at one pont and now they are staying at zero that is perfect. That is what you want to see. Once nitrites go up and then go to zero you should never see them again in a cycled tank.

Are you saying that you are dosing the ammonia up to 2 and it only goes to 1 in 24 hours or are you saying that you are just dosing up to one now and it doesn't go down.

The nitrates will continue to climb and since there is no other bacteria to eat them they have to be lowered with either lots of plants or water changes.

 

Duckweed is one of my favorite pond plants because the koi and goldfish love them. But in an aquarium, you'll be throwing out net fulls at a time. They multiply so fast that nearly all of your light will be blocked. They can also lower the oxygen exchange at the water surface hindering it's flow. Like I said, I love it for ponds, but you may want to consider some other options for your aquarium.

Oh I know, I have a plan for that too, and the extra duckweed can be made into food for snails! I just love how it looks and I've seen lots of great aquarium setups with duckweed so I wanted to try it out my current fish will be a betta and in the future I plan to have sparkling gourami's so if oxygen seems lower they can always surface for air, and they like still water anyway.

I am not sure I understand the OP. If you had nitrites at one pont and now they are staying at zero that is perfect. That is what you want to see. Once nitrites go up and then go to zero you should never see them again in a cycled tank.

Are you saying that you are dosing the ammonia up to 2 and it only goes to 1 in 24 hours or are you saying that you are just dosing up to one now and it doesn't go down.

The nitrates will continue to climb and since there is no other bacteria to eat them they have to be lowered with either lots of plants or water changes.

The former is correct, its being dosed to 2ppm and now after the water change it only goes down to 1ppm in 24hrs, instead of 0 like it did before.

And my understanding of how BB works is that ammonia goes down > nitrite goes up > nitrite goes down > nitrate goes up > nitrate is removed by water changes

And yes, the nitrites seem fine, but the ammonia is wavering which makes me think that only the first kind of bacteria (nitrosoma) is affected... Otherwise I would get nitrite readings as well, right?

 

I am not sure I understand the OP. If you had nitrites at one pont and now they are staying at zero that is perfect. That is what you want to see. Once nitrites go up and then go to zero you should never see them again in a cycled tank.

Are you saying that you are dosing the ammonia up to 2 and it only goes to 1 in 24 hours or are you saying that you are just dosing up to one now and it doesn't go down.

The nitrates will continue to climb and since there is no other bacteria to eat them they have to be lowered with either lots of plants or water changes.

Not trying to be confusing, because there are no bacteria that eats nitrates, plants and water changes are the only way to remove them. But if the beginning of the cycle, which is ammonia conversion, the animals added to the tank would be in danger of ammonia poisoning because the Nitrosomas bacteria would be working too slowly. The ammonia conversion has to be quick. Then the Nitrobacter can convert the nitrites to nitrates. The need for having enough ammonia eating bacteria is paramount to the beginning and the ongoing process.

 

The former is correct, its being dosed to 2ppm and now after the water change it only goes down to 1ppm in 24hrs, instead of 0 like it did before.

And my understanding of how BB works is that ammonia goes down > nitrite goes up > nitrite goes down > nitrate goes up > nitrate is removed by water changes

And yes, the nitrites seem fine, but the ammonia is wavering which makes me think that only the first kind of bacteria (nitrosoma) is affected... Otherwise I would get nitrite readings as well, right?

I really don't know why your tank has slowed down on converting all of the ammonia since you said your tank had completed its cycle. I am assuming from that at one point you had nitrites and then your test are showing that there are none now.

I am sure you understand how a cycle should work but no, once a tank starts producing nitrites and then those nitrites drop to zero you should never see nitrites again. The ammonia is still converting to nitrites but a fully cycled tank will do it so quickly they won't show up with the tests.

 

Well, at least you'll have fish that have auxiliary breathing methods. Cory catfish also have an auxiliary breathing method so you can even have a school of them as well to keep sunken food off the bottom. I just wanted to make sure you knew how fast they grew. Have fun and good luck.

Oh I know, I have a plan for that too, and the extra duckweed can be made into food for snails! I just love how it looks and I've seen lots of great aquarium setups with duckweed so I wanted to try it out my current fish will be a betta and in the future I plan to have sparkling gourami's so if oxygen seems lower they can always surface for air, and they like still water anyway.

 

Well, at least you'll have fish that have auxiliary breathing methods. Cory catfish also have an auxiliary breathing method so you can even have a school of them as well to keep sunken food off the bottom. I just wanted to make sure you knew how fast they grew. Have fun and good luck.

Oh I didnt know that about Corys! How cute, I'll definitely look into that

 

Oh I didnt know that about Corys! How cute, I'll definitely look into that

Yes, they don't have labyrinth organs like the Anabantoids. Instead, you'll see them occasionally zip real fast to the surface and swallow a bubble of air. Oxygen is extracted in their gut. So they can be kept with Anabantoids in low oxygen conditions.

 

I really don't know why your tank has slowed down on converting all of the ammonia since you said your tank had completed its cycle. I am assuming from that at one point you had nitrites and then your test are showing that there are none now.

I am sure you understand how a cycle should work but no, once a tank starts producing nitrites and then those nitrites drop to zero you should never see nitrites again. The ammonia is still converting to nitrites but a fully cycled tank will do it so quickly they won't show up with the tests.

Okay I understand that, but now my tank can't be called fully cycled just yet because of whatever happened
It *was* cycled, everything went as it should have, and now the first kind of BB seems to have partially died off or something..
So if there was an imbalance in the population of nitrite bacteria due to some die-off, it would show leftover nitrites that hadn't been processed, right?

Or I don't get how the nitrite bacteria works and any population of it will process nitrite in 24hrs no matter the size..?

 

They both will grow or die down to the levels available.. it takes a few days.
Where you careful during the water change to treat it before adding to tank? Did you clean the filter out?

 

They both will grow or die down to the levels available.. it takes a few days.
Where you careful during the water change to treat it before adding to tank? Did you clean the filter out?

I was, I didnt clean the filter but I did clean the gravel a little bit, that's probably what did it :/

 

Okay I understand that, but now my tank can't be called fully cycled just yet because of whatever happened
It *was* cycled, everything went as it should have, and now the first kind of BB seems to have partially died off or something..
So if there was an imbalance in the population of nitrite bacteria due to some die-off, it would show leftover nitrites that hadn't been processed, right?

Or I don't get how the nitrite bacteria works and any population of it will process nitrite in 24hrs no matter the size..?

Let me try again. Sometimes it is hard for me to write clearly enough.

A cycled tank will have 0 ammonia, 0 nitrites and some nitrates. I am assuming this is what your tests were showing at one point. The ammonia and nitrites are still there but they convert to nitrates too quickly for our tests to register them.

A newly cycled tank is still fairly delicate and it is possible that cleaning the gravel a bit too much could have thrown it slightly off balance. It is very possible that this cycle will be back on track in just a few days.

Don't be concerned about not seeing nitrites though. The concern would be if you do start seeing them.

 

Let me try again. Sometimes it is hard for me to write clearly enough.

A cycled tank will have 0 ammonia, 0 nitrites and some nitrates. I am assuming this is what your tests were showing at one point. The ammonia and nitrites are still there but they convert to nitrates too quickly for our tests to register them.

A newly cycled tank is still fairly delicate and it is possible that cleaning the gravel a bit too much could have thrown it slightly off balance. It is very possible that this cycle will be back on track in just a few days.

Don't be concerned about not seeing nitrites though. The concern would be if you do start seeing them.

Oh okay gotcha! Thank you

 

Let me try again. Sometimes it is hard for me to write clearly enough.

A cycled tank will have 0 ammonia, 0 nitrites and some nitrates. I am assuming this is what your tests were showing at one point. The ammonia and nitrites are still there but they convert to nitrates too quickly for our tests to register them.

A newly cycled tank is still fairly delicate and it is possible that cleaning the gravel a bit too much could have thrown it slightly off balance. It is very possible that this cycle will be back on track in just a few days.

Don't be concerned about not seeing nitrites though. The concern would be if you do start seeing them.

I agree, but believe you are almost there.

Just do the ammonia to 2ppm and monitor.

Bet you are a week from fully cycled.

And don’t vacuum all of the gravel, just 1/2, every 2 weeks.

 

I agree, but believe you are almost there.

Just do the ammonia to 2ppm and monitor.

Bet you are a week from fully cycled.

And don’t vacuum all of the gravel, just 1/2, every 2 weeks.

Okay, thanks

 

I agree, but believe you are almost there.

Just do the ammonia to 2ppm and monitor.

Bet you are a week from fully cycled.

And don’t vacuum all of the gravel, just 1/2, every 2 weeks.

Okay, thanks

I still think to redical water change of 90 percent dropped both un attached Nitrosomas as well as their ammonia food source. You at least still have Notrosomas in the tank since you're still getting a 1ppm conversion. Keep feeding ammonia and it will be back to normal soon. And keep in mind that a few smaller water changes over a few days is much safer than practically a complete water change.