Cycle DID crash, new filter

I did everything to the best of my capabilities and followed some of the advice on this board by adding some of the old filter parts in with the new filter hoping the cycle wouldn't crash. I had added four small danios to my lightly populated 30 gallon tank, did a water change and vacuumed real good, and within one week, I discovered my ammonia level spiked from zero to 1.0 PPM. Nitrites remain at zero, and after a 35% water change this morning, my nitrates dropped from 80 to 20 but the ammonia scares me. I used Seachem stability according to directions for 7 days prior to adding danios, and wondering what my next move is?
Another water change tomorrow?
I really don't want to lose these fish and I have a high level of experience but I've never gone through this when changing a filter...... please help!
Thank you!

 

I suspect you are experiencing a mini-cycle. Thankfully they don't last as long as a normal cycle. Changing the filter, adding more fish and deep cleaning the tank all at the same time may be what has caused it. Bacteria was lost and the bio-load was increased.

For now I recommend you keep the ammonia down as low as possible with water changes. Don't clean anything in the tank. Just remove and replace water. The bacteria should catch up fairly fast.

 

What filter parts did you move over from the old filter? Were they kept wet? Usually, anything with a high surface area will transfer over plenty of BB.

What's the complete stock list of the tank? Or, is it just the 4 danios?

Personally, when dealing with fish-in cycles, I like to keep ammonia and nitrite combined under 1 PPM - ammonia will burn any sensitive external areas, and nitrite will do some damage to internal organs (among other things). Fish tend not to do well with several different stress factors at once, so keeping both of these to a minimum is a must.

I'd add in the rest of the bottle of the Stability (I usually do this on day 1 - it won't hurt anything), and continue to do whatever water changes are necessary to keep your combined ammonia and nitrite under 1 PPM.

I also question the accuracy of your test kit, where nitrates are concerned. Typically, if you do a 35% water change with water that has 0 PPM nitrate, the nitrate in the tank will go down by 35%. You listed a 35% water change with a 75% decrease in nitrates - it could have just been a little too much of one reagent added (or not enough), but still - it raises some concern.

 

I suspect you are experiencing a mini-cycle. Thankfully they don't last as long as a normal cycle. Changing the filter, adding more fish and deep cleaning the tank all at the same time may be what has caused it. Bacteria was lost and the bio-load was increased.

For now I recommend you keep the ammonia down as low as possible with water changes. Don't clean anything in the tank. Just remove and replace water. The bacteria should catch up fairly fast.

Thanks mattgirl,
I thought I was doing good and I guess I overdid it, should have just added the fish and let it Rock and roll. Tomorrow morning I'll do another 35% change and the next day after that the same if no ammonia drop. Nitrates don't scare me as much as the ammonia. Thanks for your input and if anybody else can contribute I appreciate it.
Much thanks

What filter parts did you move over from the old filter? Were they kept wet? Usually, anything with a high surface area will transfer over plenty of BB.

What's the complete stock list of the tank? Or, is it just the 4 danios?

Personally, when dealing with fish-in cycles, I like to keep ammonia and nitrite combined under 1 PPM - ammonia will burn any sensitive external areas, and nitrite will do some damage to internal organs (among other things). Fish tend not to do well with several different stress factors at once, so keeping both of these to a minimum is a must.

I'd add in the rest of the bottle of the Stability (I usually do this on day 1 - it won't hurt anything), and continue to do whatever water changes are necessary to keep your combined ammonia and nitrite under 1 PPM.

I also question the accuracy of your test kit, where nitrates are concerned. Typically, if you do a 35% water change with water that has 0 PPM nitrate, the nitrate in the tank will go down by 35%. You listed a 35% water change with a 75% decrease in nitrates - it could have just been a little too much of one reagent added (or not enough), but still - it raises some concern.

This filter and the old filter were both AquaTech and parts are interchangeable, so as recommended by some folks on here I moved over the red plate that's in the AquaTech that they tell you never to clean because it contains all the bacteria and I did keep it wet in aquarium water while making the move.
The four Danios were just added to a tank that has one blue gourami a tiny pleco a scavenger cat and that's it. As far as the accuracy of the nitrate test kit I don't know. I shook that bottle number two until I couldn't shake it no more and I usually get pretty accurate readings but then again like I said I don't know. So I can actually add more seachem at this point?

 

To be perfectly honest I would not depend on that red piece of plastic for growing my bacteria. I ran these filters for quite a while but didn't keep that plastic piece in there I replaced both it and the cartridge with ceramic bio-media and a piece of foam. If you didn't transfer over a seeded cartridge along with that piece you left a lot of bacteria behind.

Thankfully bacteria grows on everything in our tanks so it shouldn't take long for it to replace what was lost. Just keep the ammonia down with water changes while it catches up.

 

Hi I’m still new to this forum but in the hobby over 60 years. That’s with all kinds fish and turtles. One thing for sure you will find lots of anecdotal advice. Yes it works great for the other tanks but may not work for yours. Even with good documented research there are different results when some try to interpret what they read to fit what they want to do. Without a lot more info it’s hard to say what stage your cycle was in. Unfortunately too many don’t read up on how to keep it going week after week , month after month. The good “live” nitrefying bacteria is as important as the fish. In my time being an very old timer found “no” two tank setup the same in the same room will ever have the same needs when it comes to maintenance. Just too many factor's for an individual tank. Type decorations , type and amount of substrate , all water parameters , chemicals if any , filter and media and many more than just this. Then how much good nitrifying bacteria one keeps alive and the cycle going month after month.

I found most small tanks with a general maintenance schedule is not as forgiving as a 100 gallon or larger. You stated new filter (kept some old media) is good then a 35% WC and a good vacuuming is a lot of change at once. When I had small tanks I would do filter media one week then WC the next week and even later gravel/substrate cleaning yet at another time. I found less shock to a small system giving safe time for it to adjust. With the way we all just love doing maintenance sure some will disagree but it worked decades ago and today. A large 100 gallon tank is more forgiving and may be handled different. Even the technique used to vac the substrate is important. This is to keep all that good nitrifying bacteria alive so it can do a lot of the work. I have 4” substrate and only skim the surface never digging down to the bottom. Once the cycle was started and maintained I let it (the nitrogen cycle) do its thing as mother nature only can do. Remember advice is good but one must find a balance for there own setup. No two tanks will ever need the exact same maintenance.

Best advice I have is to yes ask questions and read up a lot then discern fact that works for “your” tank. Keeping a journal will help to remember exactly what has been tried. Sounds like you started correct at first then too much was done at a giving time for your tank to handle the quick parameter change. Balance is key in this hobby and no matter what I or others say “you” must find the balance for your tank. Use info you get as a guide and tweak to fit your tanks needs.

 

To be perfectly honest I would not depend on that red piece of plastic for growing my bacteria. I ran these filters for quite a while but didn't keep that plastic piece in there I replaced both it and the cartridge with ceramic bio-media and a piece of foam. If you didn't transfer over a seeded cartridge along with that piece you left a lot of bacteria behind.

Thankfully bacteria grows on everything in our tanks so it shouldn't take long for it to replace what was lost. Just keep the ammonia down with water changes while it catches up.

I did move over a filthy filter cartridge as well. I forgot to mention that. I should be ok. I also added a lot more seachem which is harmless to the fish. Another water change tomorrow!

Hi I’m still new to this forum but in the hobby over 60 years. That’s with all kinds fish and turtles. One thing for sure you will find lots of anecdotal advice. Yes it works great for the other tanks but may not work for yours. Even with good documented research there are different results when some try to interpret what they read to fit what they want to do. Without a lot more info it’s hard to say what stage your cycle was in. Unfortunately too many don’t read up on how to keep it going week after week , month after month. The good “live” nitrefying bacteria is as important as the fish. In my time being an very old timer found “no” two tank setup the same in the same room will ever have the same needs when it comes to maintenance. Just too many factor's for an individual tank. Type decorations , type and amount of substrate , all water parameters , chemicals if any , filter and media and many more than just this. Then how much good nitrifying bacteria one keeps alive and the cycle going month after month.

I found most small tanks with a general maintenance schedule is not as forgiving as a 100 gallon or larger. You stated new filter (kept some old media) is good then a 35% WC and a good vacuuming is a lot of change at once. When I had small tanks I would do filter media one week then WC the next week and even later gravel/substrate cleaning yet at another time. I found less shock to a small system giving safe time for it to adjust. With the way we all just love doing maintenance sure some will disagree but it worked decades ago and today. A large 100 gallon tank is more forgiving and may be handled different. Even the technique used to vac the substrate is important. This is to keep all that good nitrifying bacteria alive so it can do a lot of the work. I have 4” substrate and only skim the surface never digging down to the bottom. Once the cycle was started and maintained I let it (the nitrogen cycle) do its thing as mother nature only can do. Remember advice is good but one must find a balance for there own setup. No two tanks will ever need the exact same maintenance. Keep a journal on what you do does help. Sounds like you did start a cycle just done a little too much at one time for a small tank to adjust , result a crash.



Best advice I have is to yes ask questions and read up a lot then discern fact that works for “your” tank. Keeping a journal will help to remember exactly what has been tried. Sounds like you started correct at first then too much was done at a giving time for your tank to handle the quick parameter change. Balance is key in this hobby and no matter what I or others say “you” must find the balance for you tank. Use info you get as a guide and tweak to fit your tank s need.

Your post makes a lot of sense to me as I've been keeping fish for about 55 to 60 years as well. I always had 90 gallon 100 gallon and you're right, the smaller tanks are tougher for whatever reason. I just got out of surgery not too long ago and kind of bored because there's not much for me to do so yeah, I overdid it trying to do the right thing. Vacuum gravel the water change adding the fish the new filter but I should be okay. None of the water parameters are at the scary level yet. I mean, one PPM ammonia scares me more than the 20 nitrate but another 35% change tomorrow maybe another one the day after a little more seachem and I should be good.
Have a really great day and thanks for that bundle of knowledge it really pays to read up and research as you say

To be perfectly honest I would not depend on that red piece of plastic for growing my bacteria. I ran these filters for quite a while but didn't keep that plastic piece in there I replaced both it and the cartridge with ceramic bio-media and a piece of foam. If you didn't transfer over a seeded cartridge along with that piece you left a lot of bacteria behind.

Thankfully bacteria grows on everything in our tanks so it shouldn't take long for it to replace what was lost. Just keep the ammonia down with water changes while it catches up.

mattgirl,
I just came up with another question that you might be able to help with. I've been doing a lot of internet reading on the problem I'm having right now with the ammonia now at 2.0 and many many people are saying too many water changes while using seachem can actually remove a lot of the beneficial bacteria and as long as your ammonia doesn't rise up to five or more you should just let it run its course and do weekly water changes not daily. Now I'm totally confused. Your thoughts? As some have said, the substrate and decorations and a lot of things in the tank still have the bacteria, and I'm probably going through a mini cycle. Maybe I should hold off on tomorrow's 35% change and let this roll for about a week and monitor the ammonia carefully

 

Sounds like me , hope recovering well from surgery . Past two years had five surgeries (osseous). Now a days I keep all simple especially for the fish and turtles that are part of my family and yes the nitrrifying bacteria too. Took me decades for me to let mother nature (nitrogen cycle) help my tanks. Liked chemicals in my younger days but no chemicals today !

With your experience all will be good with the plan you have. Guess me being old want to be too expeditious at times and it cost. Then step back a little and always let the tank and nature catch up to help me. See ammonia is high too. Your thinking to correct that is good. WC’s can be done will help as always . Some would do a couple 50-80% WC’s in a week. Others 10% water changes every other day until that 2ppm is down to were you want it. With your experience both can work. I prefer the latter. Do what your tank numbers tell you it needs each day until it's controllable again. No one % works for all tanks even the same size and in the same house. A 20-30% may be needed here and there. Being an old timer I done something that surprised me. It made my nitrogen cycle very stable , wish I was open to it decades ago. I made a DIY nitrogen generator , small only 1.5 liters of media but what help it’s been. After 6 decade never had numbers like I get now. Not only did my nitrates go down but it helped all my numbers go down and very stable. My ammonia is always 0.25 , the nitrite “0” , and nitrates always 5.0 the most. Gh, Kh and ph all good. This is with an OTC drip test kit. My city water is horrible ! To see better/ more accurate numbers I take samples to the national aquarium I worked at for years. Today I only volunteer (retired now) do to my health. [with there permission] There testing lab is great , an OTC price would be in the hundreds if ever put on the market. Beaks it down to accurate low numbers. Low but enough to keep a cycle going as long as I do my part correct. As old timers we know the best OTC drip kit is not accurate in very low or high numbers. The mid range is workable for this hobby.

You will get your cycle back just give it a couple days off then do your method on WC’s to get numbers controllable again. With your experience to help during those days feed once every other day , double check for melting plant material if any and monitor a lot to keep and eye on that ammonia , as you know.

Also with the seasons changing watch your water supply company. In the US law says they must tell you the water quality data every year. My company with summer changes goes from chlorine in winter then chloramine in summer which gives us headaches in this hobby. My tank is a 150 gallon stock tank with 37 juvenile fish mostly rainbows. By adult size hoping for around 80% bio load on it. Filter over three gallons bio media in a FX6 along with that small nitrogen generator. Only needs a 10-15% WC every two weeks. The filter I do open it once every three months to squeeze the one and only pad in it to protect the bio media. Also working in a lot of plants too. Also trying to get as close to a self sustaining tank as possible , that is on what I can help control. No one person can duplicate nature 100% but at my age and limitations going to do best I can .

You got this , cycle will come back . Sorry for long post couldn’t sleep and I type very slow. Know you know all this but with us getting older sometimes need to hear it again for self-assurance. Also lots of beginners around the world that follow forums and don’t post questions can hopefully understand what I’m trying to say and may help them too.

 

Sounds like me , hope recovering well from surgery . Past two years had five surgeries (osseous). Now a days I keep all simple especially for the fish and turtles that are part of my family and yes the nitrrifying bacteria too. Took me decades for me to let mother nature (nitrogen cycle) help my tanks. Liked chemicals in my younger days but no chemicals today !

With your experience all will be good with the plan you have. Guess me being old want to be too expeditious at times and it cost. Then step back a little and always let the tank and nature catch up to help me. See ammonia is high too. Your thinking to correct that is good. WC’s can be done will help as always . Some would do a couple 50-80% WC’s in a week. Others 10% water changes every other day until that 2ppm is down to were you want it. With your experience both can work. I prefer the latter. Do what your tank numbers tell you it needs each day until it's controllable again. No one % works for all tanks even the same size and in the same house. A 20-30% may be needed here and there. Being an old timer I done something that surprised me. It made my nitrogen cycle very stable , wish I was open to it decades ago. I made a DIY nitrogen generator , small only 1.5 liters of media but what help it’s been. After 6 decade never had numbers like I get now. Not only did my nitrates go down but it helped all my numbers go down and very stable. My ammonia is always 0.25 , the nitrite “0” , and nitrates always 5.0 the most. Gh, Kh and ph all good. This is with an OTC drip test kit. My city water is horrible ! To see better/ more accurate numbers I take samples to the national aquarium I worked at for years. Today I only volunteer (retired now) do to my health. [with there permission] There testing lab is great , an OTC price would be in the hundreds if ever put on the market. Beaks it down to accurate low numbers. Low but enough to keep a cycle going as long as I do my part correct. As old timers we know the best OTC drip kit is not accurate in very low or high numbers. The mid range is workable for this hobby.

You will get your cycle back just give it a couple days off then do your method on WC’s to get numbers controllable again. With your experience to help during those days feed once every other day , double check for melting plant material if any and monitor a lot to keep and eye on that ammonia , as you know.

Also with the seasons changing watch your water supply company. In the US law says they must tell you the water quality data every year. My company with summer changes goes from chlorine in winter then chloramine in summer which gives us headaches in this hobby. My tank is a 150 gallon stock tank with 37 juvenile fish mostly rainbows. By adult size hoping for around 80% bio load on it. Filter over three gallons bio media in a FX6 along with that small nitrogen generator. Only needs a 10-15% WC every two weeks. The filter I do open it once every three months to squeeze the one and only pad in it to protect the bio media. Also working in a lot of plants too. Also trying to get as close to a self sustaining tank as possible , that is on what I can help control. No one person can duplicate nature 100% but at my age and limitations going to do best I can .

You got this , cycle will come back . Sorry for long post couldn’t sleep and I type very slow. Know you know all this but with us getting older sometimes need to hear it again for self-assurance. Also lots of beginners around the world that follow forums and don’t post questions can hopefully understand what I’m trying to say and may help them too.

Thanks for the great post and don't worry about it being long and I can't sleep either it's 3:25 in the morning. My surgery was for cancer but I'm doing okay thank God. I have to carry the buckets after I fill them and dump them down the toilet then I refill them and fill the tank back up and that's tough on the back. I prefer small daily water changes but after I check my ammonia today I'll make a decision. I dumped in a half a bottle of stability yesterday after a 35% water change so we'll see what I get today. If the ammonia is higher than the two it was yesterday I might do a couple of buckets. The buckets are 2 gallons and they're hard for me to carry but I figured three buckets equal 6 gallons at a 29 or 30 gallon tank do that daily for a while and see how it goes. Hope you feeling good hope you get better stay in touch and I'll let you know how I'm doing

 

and after a 35% water change this morning, my nitrates dropped from 80 to 20

That's mathematically impossible. With a 35% waterchange the Nitrates should have dropped by about 30 to roughly 50mg/l. So one of the two readings is not correct. Either your Nitrates were lower before or the test after the wc was compromised.

 

That's mathematically impossible. With a 35% waterchange the Nitrates should have dropped by about 30 to roughly 50mg/l. So one of the two readings is not correct. Either your Nitrates were lower before or the test after the wc was compromised.

I don't know what to say to your response. I use the API Master test kit and also had it checked by the fish store. Maybe there's something in my well water. I'll have to check my well water because I've been doing this for a very long time and sometimes mathematics is wrong and sometimes the tests are compromised. I know that my numbers are correct cuz they were tested by me and the pet store, so again I don't know how to respond to your reply. I'll update as I make progress

 

Besides the fact that a lab analysis of a well once a year should be a given, how would that work out if there were nitrates in your well water? Then surely the levels in the tank wouldn't change or at least not drop that far.

I don't know what to say either, because with such basics the math is hardly wrong, so only one of the figures can be wrong, be it due to a typo, a faulty test or a wrong estimate. If the test results are confirmed, maybe you have changed more than 35%? Just saying, because I wouldn't want you to go by wrong numbers.

 

Besides the fact that a lab analysis of a well once a year should be a given, how would that work out if there were nitrates in your well water? Then surely the levels in the tank wouldn't change or at least not drop that far.

I don't know what to say either, because with such basics the math is hardly wrong, so only one of the figures can be wrong, be it due to a typo, a faulty test or a wrong estimate. If the test results are confirmed, maybe you have changed more than 35%? Just saying, because I wouldn't want you to go by wrong numbers.

I'm not going to argue with you at all maxz. It is extremely possible that the percentage of water I took out is not 35% but I did check my well water and it's zero across the board. I use it what I think is a 2 gallon bucket. I marked it off years ago at 2 gallons who knows if it is in fact 2 gallons. if I take out 8 gallons that's around 27% but I took out more and estimated at 35%. Having said that I just did an exact 20% water change and the nitrates are now 10 so from 20 they went to 10. how's that fit mathematically?

 

I also don't want to argue, I just want to help.
I was aware that there is likely nothing in your well water, because then the test results should have been higher, and not lower than calculated.

Having said that I just did an exact 20% water change and the nitrates are now 10 so from 20 they went to 10. how's that fit mathematically?

Not at all, this should have been 50% to get 20 down to 10.

Have you taken into account the volume of substrate, decorations and the like? That can make out quite a lot, so the net volume is lower than the technical max volume if there was only water in the tank. Maybe there's the problem. Would pretty much work out and explain the difference.
I have to admit I myself made the mistake to not take that into account sometimes. When I thought to have taken out 50% and actually had taken out 75% of the tank volume, as 25% of the overall volume was taken up by hardscape. It happens to all of us sometimes.

 

I did move over a filthy filter cartridge as well. I forgot to mention that. I should be ok. I also added a lot more seachem which is harmless to the fish. Another water change tomorrow!

Then it was simply the deep gravel clean and the additional bio-load. I suspect your cycle will be back on track quickly.

mattgirl,
I just came up with another question that you might be able to help with. I've been doing a lot of internet reading on the problem I'm having right now with the ammonia now at 2.0 and many many people are saying too many water changes while using seachem can actually remove a lot of the beneficial bacteria and as long as your ammonia doesn't rise up to five or more you should just let it run its course and do weekly water changes not daily. Now I'm totally confused. Your thoughts? As some have said, the substrate and decorations and a lot of things in the tank still have the bacteria, and I'm probably going through a mini cycle. Maybe I should hold off on tomorrow's 35% change and let this roll for about a week and monitor the ammonia carefully

To be perfectly honest, I would STOP adding the Stability. I don't buy that it will actually remove any bacteria though. You shouldn't need it. You should already have the right kind of bacteria in this tank. Adding the bottled stuff may very well be why your numbers aren't adding up. I guess I am old school. I believe in letting nature run its course instead of trying to rush it along with something in a bottle.

I would NEVER let the ammonia go that high in a tank with fish in it. I highly recommend you try to keep it well below one. The bacteria isn't free floating in the water so doing water changes isn't removing any. Which water conditioner are you using? Since you are using well water you may not be using one. If you aren't already using it I will recommend you get and use Seachem Prime. It is first and foremost a water conditioner much like all the rest but goes one step farther and also detoxes low amounts of ammonia.

Have you run the ammonia test on your tap water recently? If something has changed about it that may be where some of this ammonia is coming from. I'm not sure I have asked before but how long has this tank been up and running? Since you mentioned replacing you filter I just assumed it has been up and running for a while and before this happened it had been fully cycle. Is that the case?

 

I also don't want to argue, I just want to help.
I was aware that there is likely nothing in your well water, because then the test results should have been higher, and not lower than calculated.



Not at all, this should have been 50% to get 20 down to 10.

Have you taken into account the volume of substrate, decorations and the like? That can make out quite a lot, so the net volume is lower than the technical max volume if there was only water in the tank. Maybe there's the problem. Would pretty much work out and explain the difference.
I have to admit I myself made the mistake to not take that into account sometimes. When I thought to have taken out 50% and actually had taken out 75% of the tank volume, as 25% of the overall volume was taken up by hardscape. It happens to all of us sometimes.

I know you want to help and I really appreciate it this is starting to get frustrating for me. Only thing I can think of as far as the first reading is that the 80 on the nitrate was wrong. Now you brought up another point that I never even thought about.3 artificial plants, decorations like two underwater wrecked houses, there's an underwater heater in there as well. Bottom line is I'm happy with the numbers I have right now for the amount of work I did. Ammonia is 1, nitrates are 10 nitrites are zero. I dropped in a third of a bottle of stability and I'm just going to let it rock and roll for a week, test every day and hope that the filter and everything else responds and the numbers go where they're supposed to be. I really do appreciate your input. Definitely got me thinking about all different things that can make a person frustrated. Enjoy the rest of your day.

 

I really do appreciate your input.

You're welcome, didn't want to frustrate you, Sorry about that.

Enjoy the rest of your day.

You too!

 

Same here with the buckets , just 35 gallon buckets on dollies. Then got a small 200 gph pump and long hose to drain to bathroom. And to fill placed a shower arm diverter in bath https://www.amazon.com/Diverter-Sho...2FWF2GZCF7Y&psc=1&refRID=40B9NKSDC2FWF2GZCF7Y cheap dirveter on shower. Used fittings to use same tubing. Set and sit back to empty and fill for this old man.