Accidentally doing Fish-In Cycle: A few crucial Q's

Tank
What is the water volume of the tank?: 20 gallons
What type of water are you using in your tank? (tap, well, RO/DI, other): Started out tap, have switched to RO
When did you start cycling the tank?: It's complicated - I thought in December, but I'm realizing more like 2 weeks ago
What type of filtration are you running on this tank? (sponge, HOB, canister, other): HOB
If canister or HOB list all the media you are running in it. (manufactured cartridges, sponge, etc.): commercial cartridge
Do you have good water agitation/surface movement?: yep
What is the water temperature?: 74-80

If fish in cycling
What is the entire stocking of this tank? (Please list all fish and inverts): 2x White Skirt Tetras, 2x Red Eye Tetras
How often do you feed them and how much?: daily, a small pinch (everyone gets a few flakes and it's all gone in under 30 seconds)
Are they showing signs of distress? (fish hiding, staying at the top, looking pale, torn fins, etc): they're super lively and normal, a little combative with each other
Do you have live plants in the tank?: unfortunately no
If so are they healthy and actively growing?:

Products used while cycling
If this is a fishless cycle what ammonia source are you using? (fish food, Dr Tim’s ammonia, other):
If adding liquid ammonia how often do you dose ammonia in your tank and in what quantity? (1ppm, 2ppm etc.):
If using fish food as your ammonia source how much are you adding and how often?:
Are you using a dechlorinater and if so, which one?: I'm using RO, but have occasionally used Prime to treat ammonia spikes
Are you using bottled bacteria and if so, which one?: Dr Tim's
Did you add seeded media from a previously cycled tank?: no
What other products/chemicals are you using? (list them all): adding Replenish to RO water, treating 5 gallons at a time and going through about 5 gallons a week

Testing and cycling process
What was your knowledge of the nitrogen cycle before beginning to cycle your tank? (none, beginner, intermediate (please explain), advanced): I knew nothing
What do you use to test the water? (API liquid, test strips, other): API master test kit
Did you test your tap water for ammonia, nitrites, nitrates and pH, if so post the results below?:
Have you done any water changes and if so, when?: weekly in the 25% range
How much water did you change?: 25%
Did you vacuum the substrate?: not yet - there really doesn't seem to be much accumulation of anything
Did you clean your filter, filter media, decorations and/or glass?:
If using disposable cartridges have you replaced one recently?: no, but see further notes


*Parameters - Very Important
What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Tank water: 20 gals
Ammonia: 0-.25 depending
Nitrite: 0
Nitrate: 0
pH: very high - 8+

Tap water:
Ammonia: nightmare - don't use
Nitrite:
Nitrate:
pH:

Explain your cycling problem in detail. (Please give a clear explanation of what is going on, include details from the beginning of the problem leading up to now):

Here's my saga, with a few urgent "next steps" questions:

This tank was a Christmas present for my 4-year-old and we've been doing it together. Right after Christmas, it was a disaster - I added the Tetra-brand water conditioner and nitrifying bacteria, both of which claimed that we could put fish in "immediately" and still let the tank sit for about 24 hours running before we added fish. They lasted about 12 hours - three croaked overnight and one made it until almost 24 hours. This is what started my whole journey to getting a test kit and learning about the nitrogen cycle. I immediately saw that the water was very high in ammonia - deep rich green on the test kit - and that's clearly what had done them in in spite of us having added the water conditioner and nitrifying bacteria. We were both a bit traumatized so we let the tank sit for about a month, just running, empty, while I studied up on all of the nitrogen cycle in my spare time. I incorrectly (?) assumed that because the tank was already high in ammonia and we had added the nitrifying bacteria, it was just cycling on its own during that month, so I didn't test until we were ready to try again 2 weeks ago. I tested everything, all looked good, and I even took water with me to my LFS (an amazing one, maybe best in the state and about 5 minutes away!) to have them sign off on it. I brought home our current four fish and they've been great - they're very lively and "normal" for the past two weeks.

As I've studied up on the nitrogen cycle for the past 2 weeks since we've had them, I've become convinced that the tank has never cycled and now we're in the unfortunate and stressful position of doing a Fish-In cycle. The reason I think that it's never cycled is that I'm reading 0 nitrates and nitrites in spite of the ammonia creeping up every few days, and if it had cycled it seems that we'd see more activity on those two nitrogen metrics than absolutely nothing. I've been getting the ammonia out with a combination of 20--25% water changes about once a week at the minimum (or whenever the ammonia in the test kit creeps past "pale yellow" to "yellow green"), sometimes twice a week. We're feeding fairly lightly - a few flakes per fish once a day, with the whole pinch gone in 30 seconds or less.

That local fish stores is great, but we've gotten conflicting advice depending on who we talk to there. Based on my newfound knowledge and their advice, here's what else we've done in the past few weeks:

- Switched over to using RO water instead of trying to treat tap, since our tap is apparently loaded with chloramine and the store is 5 minutes away with cheap RO fills. Adding Replenish to the RO to "replenish minerals that get lost in the RO process."
- Added Dr Tim's One and Only in the past week to help the cycle get kickstarted / "can't hurt"
- Dosed Prime when doing water changes because it supposedly helps with the ammonia and slime coat but also doesn't prevent that ammonia from getting the cycle going with the bacteria

Whew, ok. So the fish seem like they're doing great but this has taken up a lot of time, mental, and physical energy. Here's where I need some expert guidance:

1. Are we doing the right things? Anything really misguided or mixed-up in there? Is it just the cycle waiting game at this point or is there something we could do better to help get it going?

2. The cheap HOB filter that came with the tank kit started backing up and overflowing (not onto the ground, but overflowing its little relief overflow back into the tank) in that month that we didn't even have fish in the tank. I've tried basically everything - pulling out the cartridge, wringing it out in tank water and putting it back, etc. and it's back to backing up within a day each time. Any idea why, especially since we didn't even have fish in the tank when it started? I've started a replacement cartridge soaking in the chamber next to it and plan to swap them out in about 2 weeks when the replacement has been properly colonized. I also have another thread going where I think I'm going to just swap this filter out entirely for a different one that gets good reviews and seems much more maintainable.

3. There's some fine white slime on surfaces in the tank that grew over the course of that fishless month - on the decorations and rocks, and there are some occasional stationary blobs of it on the substrate that almost look like little jellyfish (about the size of a dime). During the fishless month, I took this as a sign that the bacteria was in there working and growing some biology and it didn't seem bad, but now I'm concerned about it and am reading different and conflicting things about "white mold" in tanks, but I'm not sure if that's what it is or not. I slurped out the two blobs during this last water change. Is this something to be concerned about?

Thanks so much for any help - I know I wrote a novel, but I feel like we're at a crossroads right now and I'm trying to keep these little buddies alive while we get this thing established.

 

Did ammonia ever go higher than 0.25ppm (in the 'second' cycle)?

 

Tank
What is the water volume of the tank?: 20 gallons
What type of water are you using in your tank? (tap, well, RO/DI, other): Started out tap, have switched to RO
When did you start cycling the tank?: It's complicated - I thought in December, but I'm realizing more like 2 weeks ago
What type of filtration are you running on this tank? (sponge, HOB, canister, other): HOB
If canister or HOB list all the media you are running in it. (manufactured cartridges, sponge, etc.): commercial cartridge
Do you have good water agitation/surface movement?: yep
What is the water temperature?: 74-80

If fish in cycling
What is the entire stocking of this tank? (Please list all fish and inverts): 2x White Skirt Tetras, 2x Red Eye Tetras
How often do you feed them and how much?: daily, a small pinch (everyone gets a few flakes and it's all gone in under 30 seconds)
Are they showing signs of distress? (fish hiding, staying at the top, looking pale, torn fins, etc): they're super lively and normal, a little combative with each other
Do you have live plants in the tank?: unfortunately no
If so are they healthy and actively growing?:

Products used while cycling
If this is a fishless cycle what ammonia source are you using? (fish food, Dr Tim’s ammonia, other):
If adding liquid ammonia how often do you dose ammonia in your tank and in what quantity? (1ppm, 2ppm etc.):
If using fish food as your ammonia source how much are you adding and how often?:
Are you using a dechlorinater and if so, which one?: I'm using RO, but have occasionally used Prime to treat ammonia spikes
Are you using bottled bacteria and if so, which one?: Dr Tim's
Did you add seeded media from a previously cycled tank?: no
What other products/chemicals are you using? (list them all): adding Replenish to RO water, treating 5 gallons at a time and going through about 5 gallons a week

Testing and cycling process
What was your knowledge of the nitrogen cycle before beginning to cycle your tank? (none, beginner, intermediate (please explain), advanced): I knew nothing
What do you use to test the water? (API liquid, test strips, other): API master test kit
Did you test your tap water for ammonia, nitrites, nitrates and pH, if so post the results below?:
Have you done any water changes and if so, when?: weekly in the 25% range
How much water did you change?: 25%
Did you vacuum the substrate?: not yet - there really doesn't seem to be much accumulation of anything
Did you clean your filter, filter media, decorations and/or glass?:
If using disposable cartridges have you replaced one recently?: no, but see further notes


*Parameters - Very Important
What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Tank water: 20 gals
Ammonia: 0-.25 depending
Nitrite: 0
Nitrate: 0
pH: very high - 8+

Tap water:
Ammonia: nightmare - don't use
Nitrite:
Nitrate:
pH:

Explain your cycling problem in detail. (Please give a clear explanation of what is going on, include details from the beginning of the problem leading up to now):

Here's my saga, with a few urgent "next steps" questions:

This tank was a Christmas present for my 4-year-old and we've been doing it together. Right after Christmas, it was a disaster - I added the Tetra-brand water conditioner and nitrifying bacteria, both of which claimed that we could put fish in "immediately" and still let the tank sit for about 24 hours running before we added fish. They lasted about 12 hours - three croaked overnight and one made it until almost 24 hours. This is what started my whole journey to getting a test kit and learning about the nitrogen cycle. I immediately saw that the water was very high in ammonia - deep rich green on the test kit - and that's clearly what had done them in in spite of us having added the water conditioner and nitrifying bacteria. We were both a bit traumatized so we let the tank sit for about a month, just running, empty, while I studied up on all of the nitrogen cycle in my spare time. I incorrectly (?) assumed that because the tank was already high in ammonia and we had added the nitrifying bacteria, it was just cycling on its own during that month, so I didn't test until we were ready to try again 2 weeks ago. I tested everything, all looked good, and I even took water with me to my LFS (an amazing one, maybe best in the state and about 5 minutes away!) to have them sign off on it. I brought home our current four fish and they've been great - they're very lively and "normal" for the past two weeks.

As I've studied up on the nitrogen cycle for the past 2 weeks since we've had them, I've become convinced that the tank has never cycled and now we're in the unfortunate and stressful position of doing a Fish-In cycle. The reason I think that it's never cycled is that I'm reading 0 nitrates and nitrites in spite of the ammonia creeping up every few days, and if it had cycled it seems that we'd see more activity on those two nitrogen metrics than absolutely nothing. I've been getting the ammonia out with a combination of 20--25% water changes about once a week at the minimum (or whenever the ammonia in the test kit creeps past "pale yellow" to "yellow green"), sometimes twice a week. We're feeding fairly lightly - a few flakes per fish once a day, with the whole pinch gone in 30 seconds or less.

That local fish stores is great, but we've gotten conflicting advice depending on who we talk to there. Based on my newfound knowledge and their advice, here's what else we've done in the past few weeks:

- Switched over to using RO water instead of trying to treat tap, since our tap is apparently loaded with chloramine and the store is 5 minutes away with cheap RO fills. Adding Stability to the RO to "replenish minerals that get lost in the RO process."
- Added Dr Tim's One and Only in the past week to help the cycle get kickstarted / "can't hurt"
- Dosed Prime when doing water changes because it supposedly helps with the ammonia and slime coat but also doesn't prevent that ammonia from getting the cycle going with the bacteria

Whew, ok. So the fish seem like they're doing great but this has taken up a lot of time, mental, and physical energy. Here's where I need some expert guidance:

1. Are we doing the right things? Anything really misguided or mixed-up in there? Is it just the cycle waiting game at this point or is there something we could do better to help get it going?

2. The cheap HOB filter that came with the tank kit started backing up and overflowing (not onto the ground, but overflowing its little relief overflow back into the tank) in that month that we didn't even have fish in the tank. I've tried basically everything - pulling out the cartridge, wringing it out in tank water and putting it back, etc. and it's back to backing up within a day each time. Any idea why, especially since we didn't even have fish in the tank when it started? I've started a replacement cartridge soaking in the chamber next to it and plan to swap them out in about 2 weeks when the replacement has been properly colonized. I also have another thread going where I think I'm going to just swap this filter out entirely for a different one that gets good reviews and seems much more maintainable.

3. There's some fine white slime on surfaces in the tank that grew over the course of that fishless month - on the decorations and rocks, and there are some occasional stationary blobs of it on the substrate that almost look like little jellyfish (about the size of a dime). During the fishless month, I took this as a sign that the bacteria was in there working and growing some biology and it didn't seem bad, but now I'm concerned about it and am reading different and conflicting things about "white mold" in tanks, but I'm not sure if that's what it is or not. I slurped out the two blobs during this last water change. Is this something to be concerned about?

Thanks so much for any help - I know I wrote a novel, but I feel like we're at a crossroads right now and I'm trying to keep these little buddies alive while we get this thing established.

There are no minerals in RO water and Stability does not replenish it. How did pH get to 8+? Are you using aragonite gravel? It would look like white pebbles.

All HOBs clog, I don't like them for this reason. For a simple filter just use a sponge filter, but they take up a lot of space in small tanks.

The slime is fine, just signs of a new tank. Feed lightly and water change and your fish can still survive. Your tank might be already or close to cycled. I would look up local water reports and see what your tap parameters are. For now just keep using RO water.

 

There are no minerals in RO water and Stability does not replenish it.

If you read op's post in full, there is a part where op said op used Replenish to replenish RO water. Stability in the second instance is most likely a typo.

 

If you read op's post in full, there is a part where op said op used Replenish to replenish RO water. Stability in the second instance is most likely a typo.

Ah okay that makes more sense. It doesn't seem to have any bicarbonates so that's still an issue. Either way, this is just paying for expensive tap water

 

Welcome to Fishlore!

It sounds like you are on the right track with how you are cycling. Changing water when the ammonia is a little green is right on. Using the Prime.

The white film is biofilm its nothing to worry about. It's a good thing. The blobs on the bottom could be food decaying? Pics would help.

The overflowing filter ...maybe cut a slit and dig the carbon out. That may help. It's probably used up anyway.

 

If you read op's post in full, there is a part where op said op used Replenish to replenish RO water. Stability in the second instance is most likely a typo.

My bad - typo. I’ll update it.

Did ammonia ever go higher than 0.25ppm (in the 'second' cycle)?

Not higher - that’s when I intervene.

 

Thank you for going into all the details. It really does help us help you. As we talked about in your other thread getting a better filter should help. As long as you move the media (cartridge) from to old filter over to the new one it shouldn't affect the cycling process. You may also find your cycle progressing quickly once you have sufficient filtration. During the time the tank was running with no fish some bacteria was growing in there. Since the fish have only been in there for 2 weeks I actually think it is just a matter of better filtration and time.

As long as the ammonia is .5ppm or less you can hold off on a water change. Add enough Prime to treat the full 20 gallons every other day. It is going to keep the ammonia detoxed and protect your fish. If it goes higher than that get it back down by changing out half the water.

One thing I will ask, are you 100% sure you are doing the nitrate test correctly. Bottle number 2 needs to be shaken really really well. The ingredients separate and some of it sticks to the bottom of the bottle. When I use mine I bang it against the palm of my hand while shaking for a minute or more right before each use. I would really expect to be seeing some nitrates by now.

Your high pH isn't a problem so that is one thing you don't have to be concerned about. I am kinda curious as to how it is that high if you are buying RO water though. Normally RO water has a pH of less than 7. Do you have anything like limestone, crushed coral or anything along those lines in the tank that could be raising the pH level?

 

Not higher - that’s when I intervene.

It is quite common for ammonia to register 0.25ppm, even in well-established tanks.

Given you let ammonia be and left it for a month initially, there is a high possibility that your tank is cycled, at least for the four fish you currently have. With that said, it is not really able to be known if the 0.25ppm reading you have is truly that, or if it is just a false positive reading common for test kits (not just the API) to register.

My suggestion is actually to see if ammonia actually rise higher than 0.5ppm, if ever. If it does, then yeah continue with the water changes. But if not, your tank could actually be cycled, yeah.

 

3. There's some fine white slime on surfaces in the tank that grew over the course of that fishless month - on the decorations and rocks, and there are some occasional stationary blobs of it on the substrate that almost look like little jellyfish (about the size of a dime). During the fishless month, I took this as a sign that the bacteria was in there working and growing some biology and it didn't seem bad, but now I'm concerned about it and am reading different and conflicting things about "white mold" in tanks, but I'm not sure if that's what it is or not. I slurped out the two blobs during this last water change. Is this something to be concerned about?

I really don't think slime is anything to be concerned about. I suspect it is just harmless bio-film. It happens quite often in a new tank. Siphon out what you can when doing your water changes.

 

Thank you for going into all the details. It really does help us help you. As we talked about in your other thread getting a better filter should help. As long as you move the media (cartridge) from to old filter over to the new one it shouldn't affect the cycling process. You may also find your cycle progressing quickly once you have sufficient filtration. During the time the tank was running with no fish some bacteria was growing in there. Since the fish have only been in there for 2 weeks I actually think it is just a matter of better filtration and time.

As long as the ammonia is .5ppm or less you can hold off on a water change. Add enough Prime to treat the full 20 gallons every other day. It is going to keep the ammonia detoxed and protect your fish. If it goes higher than that get it back down by changing out half the water.

One thing I will ask, are you 100% sure you are doing the nitrate test correctly. Bottle number 2 needs to be shaken really really well. The ingredients separate and some of it sticks to the bottom of the bottle. When I use mine I bang it against the palm of my hand while shaking for a minute or more right before each use. I would really expect to be seeing some nitrates by now.

Your high pH isn't a problem so that is one thing you don't have to be concerned about. I am kinda curious as to how it is that high if you are buying RO water though. Normally RO water has a pH of less than 7. Do you have anything like limestone, crushed coral or anything along those lines in the tank that could be raising the pH level?

Thanks for the thoughtful response! I think I’m doing nitrate right but I will go absolutely nuts this time and see if it makes a difference.

And that’s interesting and great news about the ammonia - I got spooked by “any and all ammonia is deadly for your fish” rhetoric online. I’ll see what happens as we approach .5 instead of panicking at .25.

The initial hardness comes from our tap water (the first 20 gallon fill) and I’ve only rotated 10 gallons of RO into that as of today. Assuming it’ll come down with the next month of partial water changes at 5 gallons of RO a week?

 

Thanks for the thoughtful response! I think I’m doing nitrate right but I will go absolutely nuts this time and see if it makes a difference.

You are so very welcome. When I first got my API kit I read I had to shake bottle #2 really well but overlooked the instructions to shake the test tube for a full minute after adding drops from each of the 2 bottles. Since that happened I found it is easy to over look the fine details from time to time so always have to ask. Guess I am hoping I am not the only one that overlooks an important step

that’s interesting and great news about the ammonia - I got spooked by “any and all ammonia is deadly for your fish” rhetoric online. I’ll see what happens as we approach .5 instead of panicking at .25.

Some folks seem to never see a true zero reading for ammonia. No matter what they do they always see a very slight tinge of green. If that is what is happening with you we want to see more than .25 before getting concerned. If we don't then the fish are safe.

The initial hardness comes from our tap water (the first 20 gallon fill) and I’ve only rotated 10 gallons of RO into that as of today. Assuming it’ll come down with the next month of partial water changes at 5 gallons of RO a week?

Gotcha, yes, over time with water changes with the RO water the pH is going to drop in this tank and at one point should level out at the level of the RO water. Doing 25% water changes are a good idea until the pH in the tank is the same as the RO water. After that you can safely do larger water changes.

 

You are so very welcome. When I first got my API kit I read I had to shake bottle #2 really well but overlooked the instructions to shake the test tube for a full minute after adding drops from each of the 2 bottles. Since that happened I found it is easy to over look the fine details from time to time so always have to ask. Guess I am hoping I am not the only one that overlooks an important step

Some folks seem to never see a true zero reading for ammonia. No matter what they do they always see a very slight tinge of green. If that is what is happening with you we want to see more than .25 before getting concerned. If we don't then the fish are safe.

Gotcha, yes, over time with water changes with the RO water the pH is going to drop in this tank and at one point should level out at the level of the RO water. Doing 25% water changes are a good idea until the pH in the tank is the same as the RO water. After that you can safely do larger water changes.

OP is not just using RO water though, it's RO + Seachem Replenish if I understand correctly? But the problem is Replenish is only GH, so KH will still need to be added or the pH will swing drastically. But if hes adding GH and KH to RO water then he is simply buying 3 products to obtain tap water...which is a big waste of money. If he uses RO water by itself, he can potentially setup an acidic blackwater tank with lots of leaf litter and diftwood, but that doesn't seem to be the direction he is taking?

 

OP is not just using RO water though, it's RO + Seachem Replenish if I understand correctly? But the problem is Replenish is only GH, so KH will still need to be added or the pH will swing drastically. But if hes adding GH and KH to RO water then he is simply buying 3 products to obtain tap water...which is a big waste of money. If he uses RO water by itself, he can potentially setup an acidic blackwater tank with lots of leaf litter and diftwood, but that doesn't seem to be the direction he is taking?

Apparently op is not using tap water because the ammonia reading for said water is crazy.

 

I am definitely curious to test treating my tap water with Prime and seeing what it tests after 24 hrs sitting in a bucket. What got me started on this whole RO mess was treating my tap water with basic PetSmart water conditioner, letting it sit out for 24 hours and then it still testing 2+ PPM for ammonia. After some convos with the local fish store it’s apparently a known thing around here due to the heavy chloramine use?

 

I am definitely curious to test treating my tap water with Prime and seeing what it tests after 24 hrs sitting in a bucket. What got me started on this whole RO mess was treating my tap water with basic PetSmart water conditioner, letting it sit out for 24 hours and then it still testing 2+ PPM for ammonia. After some convos with the local fish store it’s apparently a known thing around here due to the heavy chloramine use?

Hmm that means there would be at least 2ppm chloramine...which is not too bad. My tap water has about 1.5-2.5ppm chloramine and I use it without issue.

To be safe just keep using the RO water. Perhaps in the future, a water holding tank can be setup to process whatever ammonia is in tap water.

 

I am definitely curious to test treating my tap water with Prime and seeing what it tests after 24 hrs sitting in a bucket. What got me started on this whole RO mess was treating my tap water with basic PetSmart water conditioner, letting it sit out for 24 hours and then it still testing 2+ PPM for ammonia. After some convos with the local fish store it’s apparently a known thing around here due to the heavy chloramine use?

Prime isn't going to remove the ammonia. You will get the same reading with or without adding Prime. Still not a bad idea to leave some sitting for 24 hours though. Run all the test on it after 24 hours to get a baseline number. It is possible you will be able to use your tap water after the tank is firmly established.

I really do think a better filter and time will get this tank cycled fairly fast. By fast I am talking about another couple of weeks. The better filter will be pulling the ammonia through the media better than the filter you are using now.

 

Prime isn't going to remove the ammonia. You will get the same reading with or without adding Prime. Still not a bad idea to leave some sitting for 24 hours though. Run all the test on it after 24 hours to get a baseline number. It is possible you will be able to use your tap water after the tank is firmly established.

I really do think a better filter and time will get this tank cycled fairly fast. By fast I am talking about another couple of weeks. The better filter will be pulling the ammonia through the media better than the filter you are using now.

Thanks so much! Picking the filter up today and definitely going to experiment with the tap water. Of course all of this now has me going “wait a second - I drink this stuff!!!” LOL

 

Thanks so much! Picking the filter up today and definitely going to experiment with the tap water. Of course all of this now has me going “wait a second - I drink this stuff!!!” LOL

yep, drinking water with ammonia would give me pause too. I do have to think it is within safe levels for human consumption though. It is possible I may be too trusting in that regard

 

Im glad my tap just has chlorine in it. My husband says it makes ice taste funny still though.

 

Good news - we have Nitrites for the first time today! Ammonia seems to be very low - slightly greenish yellow - but finally I’m seeing nitrite activity. My plan is to change about 20% water on schedule this weekend.

 

Nitrates or Nitrites? Nitrites are just as bad as ammonia for the fish. What reading are you getting?

 

Nitrates or Nitrites? Nitrites are just as bad as ammonia for the fish. What reading are you getting?

Nitrites. It’s hard to tell by color gradients, but somewhere on the way to .25 PPM. This is the first time I’ve seen any nitrites at all on readings but I take it as a sign that something is actually happening chemically instead of ammonia which I just mechanically remove via water changes. I added some Prime per Mattgirl and I’m planning to test over the next few days and then do my 20-25% water change this weekend. Does that seem like the right move?

 

Nitrites are just as poisonous as ammonia , as stated in post #22 by Stargirl.

I would be doing a water change today and another in the weekend BigSniff.

I don’t want to interfere with what others have written but it seems to me 20%-25% is a little on the small side for a water change when you have fish in the tank?

 

I just tested about 8 hours later and I’m reading zero nitrites now. Do they slightly rise and fall like that?

 

As long as you always give the test tube a quick rinse before and after each test, that result is good news.

I can’t say a rise and fall in nitrites is normal in a fish in cycle. It is for your tank.

The bacteria you have are still low in numbers. In time the tank will have enough bacteria to take care of any small fluctuations in ammonia ( and nitrites) .

A small water change will not do any harm to the fish or the bacteria. Temperature matched conditioned water of course.

 

Nitrites. It’s hard to tell by color gradients, but somewhere on the way to .25 PPM. This is the first time I’ve seen any nitrites at all on readings but I take it as a sign that something is actually happening chemically instead of ammonia which I just mechanically remove via water changes. I added some Prime per Mattgirl and I’m planning to test over the next few days and then do my 20-25% water change this weekend. Does that seem like the right move?

When doing a fish in cycle we don't do water changes on a set schedule. We let the test results guide us as to when to do a water change. When we start seeing nitrites they don't normally go up and down unless we are lowering them with a water change. normally they rise and when they drop to zero we never see them again.

We want to keep the total amount of ammonia plus nitrites well below one. If the number gets up close to one it is time to change out half the water to get them down as close to zero as we can. As long as we do this the fish should never be in any danger.

If you are seeing nitrites and are no longer seeing ammonia it means your cycle is well on its way to being done. You are mechanically removing ammonia with water changes but the bacteria in the tank is taking care of it for you now. If you are in fact seeing only .25 nitrites they are in the safer zone. Keep both ammonia and nitrites down to .25 or less with water changes and before much longer both should zero out and all you will be left with are nitrates.