Cycling an Aquarium
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Your nitrate is probably a result of nitrite interference - real nitrate should be close to zero.
Sincerely Lasse
Sincerely Lasse
Lol, he tested everyday, but not going to contaminate his build thread with such piffle. He also added food every other day, which is more reasonable than the suggestion that processing two pinches of flake a month is acceptable, that's how we used to do it instead of rotting shrimp.To cycle that system without testing simply add two small ground up pinches of fish food and wait 30 days. It'll be cycled, we have threads on file using this testless method:
Build Thread - My SPS Waterbox Peninsula Mini 15
Hi all. Long time member (I think I joined right around when R2R started or took off years ago) but got out of the hobby for about 6 years and now I am back! I don't see many build threads for the PM 15 (mostly the 25) so thought I'd share my journey here. This post will be a bit behind...www.reef2reef.com
If you add bottle bac it'll speed up the ready time.
Edit - would love to know what the insult was that you edited out on his thread, seemed to upset him a tad.
Last edited:
yambeezy23
Community Member
Hi everyone! Need some direction on what to do
Started my cycle on January 28th with dr Tim’s and dr Tim’s ammonia. Dosed ammonia once per instructions.
Just a couple days ago my ammonia finally went to zero but my nitrite has been holding a steady at 1 or more (Red Sea test doesn’t go past 1).
Do I need to do anything with my cycle like add more bacteria because my nitrite hasn’t gone away or just leave it alone ?
Thanks in advance
Waterbox 35.2 for reference
Started my cycle on January 28th with dr Tim’s and dr Tim’s ammonia. Dosed ammonia once per instructions.
Just a couple days ago my ammonia finally went to zero but my nitrite has been holding a steady at 1 or more (Red Sea test doesn’t go past 1).
Do I need to do anything with my cycle like add more bacteria because my nitrite hasn’t gone away or just leave it alone ?
Thanks in advance
Waterbox 35.2 for reference
ScottJ
Valuable Member
Ignore nitrite, don't even test for it. Test for nitrate, when ammonia is 0 (within test error) and nitrate is present, you're good to go. Takes about 10 days if you use bottles bac.
Ps, the search bar will give you more info on cycling than you can even read before the the tank is ready
Please read these threads
www.reef2reef.com
and
www.reef2reef.com
You will read nitrate but it is because you have nitrite in your system. Nitrite interfere with the nitrate measurement - give false nitrate measurement. Your system has halt just before the second step - nitrite ->nitrate.
Nitrite is not particularly acutely toxic to saltwater fish that´s true, however, we know very little about sub-lethal effects and how it works as a stressor. IMO even saltwater fish should not be put into a system with known high nitrite levels
In your case I would take advances of the findings in the first thread above and add som "live" sand either
Nature's Ocean (live bagged sand) or Caribsea Arag-Alive (live bagged sand)
Sincerely Lasse
Not all Cycling Bacteria are created equal. Who's who, and what do they need?
My hypothesis is that there are very different types of Bacteria that are being used to "cycle" tanks to prevent ammonia accumulation, and it's not entirely clear which products contain which group, and it's also poorly understood what the requirements are for one of these groups to do their...
www.reef2reef.com
and
The importance of nitrite measurements in a reef aquarium
There have been a lot of threads about nitrification and cycling lately. IMO - the most important measurements tool you have in order to indicate if your cycle is done or not is the nitrite level. It is a rather stable tool and will give stable results with few interferences. One of the myths...
www.reef2reef.com
You will read nitrate but it is because you have nitrite in your system. Nitrite interfere with the nitrate measurement - give false nitrate measurement. Your system has halt just before the second step - nitrite ->nitrate.
Nitrite is not particularly acutely toxic to saltwater fish that´s true, however, we know very little about sub-lethal effects and how it works as a stressor. IMO even saltwater fish should not be put into a system with known high nitrite levels
In your case I would take advances of the findings in the first thread above and add som "live" sand either
Nature's Ocean (live bagged sand) or Caribsea Arag-Alive (live bagged sand)
Sincerely Lasse
JdubC
Community Member
Gearing up to start my first reef tank. Super excited. Planning on using dry rock for the aquascape and a fish less cycle with Dr. Tim’s.
I am curious, however, would it be worthwhile to put some pieces of live rock in my sump to help seed the cycle as well? Would this just be redundant?
I am curious, however, would it be worthwhile to put some pieces of live rock in my sump to help seed the cycle as well? Would this just be redundant?
ScottJ
Valuable Member
Live rock is always a good idea. Are you talking from the Ocean live rock, or wet rock from another tank? Ocean rock is better, but from another tank is beneficial also.
MadHatter'sReef
Community Member
Great read!Cycling a new aquarium.
One of the earliest topics a new aquarium hobbyist needs to learn is how to properly cycle their aquarium. There is a ton of information on this process and many different methods on how to accomplish it. There are many different chemical and biological cycles our tank goes through as it matures but this addresses the one most commonly discussed.
What is cycling?
The term cycling comes from the process known as the “Nitrogen Cycle”. When a plant or animal decays, or an animal expels waste, nitrogen is released. In our aquariums we initially see this as ammonia. Bacteria converts the ammonia to nitrite and then to nitrate. When we have enough bacteria to quickly convert ammonia to nitrate, we say that our tank has cycled. This is deceiving because the process doesn’t stop at this point and it is never complete. For this reason we need to think of this as establishing a large enough bacteria population to support fish, not completing a cycle.
Ammonia is a waste product of a fish’s cellular activity which is expelled through their gills. If the ammonia in the water is higher than in their blood it cannot be released and builds up in the fish causing cell damage. Nitrosomonas bacteria use ammonia as food and convert it to nitrite.
Nitrite is also harmful to fish. In a fish, nitrites hinder the ability of its blood to carry oxygen. Nitrites are a serious issue in fresh water systems. The same receptors in a fish that would absorb nitrites have a higher affinity for chlorides. The chlorides in saltwater block nitrites from being absorbed and protects the fish in marine systems. We rely on a different species of bacteria, Nitrobacter, to convert nitrite to nitrate.
Nitrates are relatively harmless for fish unless it reaches very high levels. Nitrates leaves our tank in any number of ways. We get rid of it via water changes. Algae and some corals can consume it as food.
The last part of the cycle is when nitrate is converted to nitrogen gas. This is done by anaerobic bacteria inside porous rock or within deep sand beds. Not every aquarium has the necessary conditions for this to occur
What conditions do I need for the cycle to occur?
To provide a good environment for the bacteria, we only need to make sure they are wet, oxygenated, and the pH is between 6.5 and 8.5. They will grow best at a temperature close to where we keep our tanks however they will still survive and reproduce at temperatures between 45F and 100F. We also want to monitor ammonia during this process. If ammonia gets over 5ppm it can slow down the rate bacteria reproduce. Above 10ppm it can stall the cycle.
How does rock affect the cycle?
The rock in a marine tank is the core of its filtration system. We use porous rock to provide as much surface area as possible for bacteria to grow on. The water flowing around the rock brings the ammonia and nitrites to the bacteria. If the rock is large enough it may have anaerobic bacteria deep within it that can convert the nitrates to nitrogen gas.
There are many types of rock that are available in our hobby. I won’t get into all of the different types but I do want to address how dry and live rock impacts the cycle
Dry rock is just that. It is rock that has been dried out and has nothing alive on it. Dry rock can be “clean” where it is considered safe to put directly into an aquarium. If it is not clean it will need to be cured prior to use. Either way, it will not contain nitrifying bacteria. This isn’t a problem as nitrifying bacteria are everywhere and it would be impossible to keep them out of our aquarium even if we wanted to.
Live rock is rock that does have living bacteria on it. The main reason to use live rock is to speed up the cycling process. Just like with dry rock, not all live rock is ready to put immediately in an aquarium. For simplicity I am going to put live rock in 2 broad categories. If your live rock came directly out of a marine system and is kept submerged in quality water during transport you can put it directly into your tank. If the rock was exposed to air or shipped damp then it needs to be cured prior to use. The bacteria on this rock will be fine but other living things may have died and should be removed prior to putting it in your tank.
How do I feed the bacteria?
There are many different takes on this and it is largely a matter of opinion. So here are the most common ways from worst to best in my opinion.
Adding a fish – while it will work as an ammonia source, why would you make a fish suffer in an environment in which it can’t properly shed its toxins?
Ghost feeding – When you add food to the tank you are adding much more than just what breaks down to ammonia. While none of it will be a problem, other than possibly algae, this is an uncontrolled process.
Adding a shrimp – The shrimp will decay and create ammonia, but again, this is an uncontrolled process. How much ammonia will this add and how quickly? I don’t know.
Dosing pure ammonia – This is the only method I will ever use in the future. You can measure exactly how much you need to add to achieve a specific level of ammonia. You can measure just how quickly your bacteria consume it to judge the health of your bacteria population.
How do I recommend doing it?
I’m glad you asked! I’ll start from the point where the tank is set up, filled, has flow, and temperature is in the normal range. It doesn’t matter if you used live or dry rock.
I will either use pure ammonia or ammonium chloride to raise the total ammonia to 2ppm. I will test for ammonia, nitrites, and nitrates daily until ammonia is near 0ppm. I will then dose it back up to 2ppm while continuing daily tests. I will repeat this process in a smaller tank until ammonia goes from 2ppm to 0ppm within 24 hours. In tanks that are 90g+ that will be stocked slowly I will only dose to 1ppm ammonia after the initial dose and consider it cycled when it drops from 1ppm to 0ppm in 24 hours. This is to limit nitrates in larger tanks. Keep in mind that a 120g system that drops 1ppm in a day can support more fish than a 40g tank that drops 2ppm in a day.
But I still have questions!
Ok, let me see if I can answer some of the more common ones.
If nitrifying bacteria are everywhere, why are “bacteria in a bottle” products so popular?
Nitrifying bacteria are everywhere so that isn’t the problem. Some bacteria can double their population in 20 minutes. Luck would have it that these tend to be the more poisonous kind. Nitrifying bacteria are relatively slow reproducers and it takes between 8 and 24 hours for them to double their population. If you start with dry rocks it can take a month or two to produce enough bacteria to support even a few small fish. Using bacteria in a bottle instantly provides a larger source of bacteria to speed up the front end of this process.
My cycle went fine for 3 weeks but now it stalled, what happened?
It could be any number of things. Did you let your ammonia go to high? Do you have a pH issue?
Your nitrifying bacteria may be being outcompeted for resources with other bacteria and/or algae. They may process ammonia fine at first but they will eventually go dormant. When this happens, your cycle will stall until a more marine friendly bacterium reproduces enough to begin the cycling process again. Bacteria in your tank are in constant competition for food. Eventually the one best suited to your specific system will thrive.
Can I vacuum out too much bacteria by cleaning? Will cleaning my sand bed cause my tank to cycle?
No, you cannot hurt your bacteria population by routine vacuuming or water changes. These bacteria are very difficult to remove from solid surfaces and would be difficult to remove even with scrubbing.
If your sand bed is very dirty you may cause an ammonia spike that is larger than your current bacteria population can handle but you haven’t done any harm to your bacteria population.
Can I use old tank water to cut back on my new tanks cycle time?
You can, but it won’t help much. The majority of the bacteria is going to be growing on hard surfaces, not floating in the water. There will be some, however, so you will likely introduce a strain of bacteria into your new tank that will eventually work very well.
I never measured any nitrite during my cycle, is this a problem?
No, odds are this is not a problem. It is possible that you had a larger initial population of Nitrobacter bacteria (nitrite eaters) compared to Nitrosomonas bacteria (ammonia eaters). In this case the nitrite was processed to nitrate almost as soon as it was produced.
Another possibility is that you have a large population of Nitrospira bacteria. These bacteria convert ammonia into nitrite and then to nitrate within the same cell structure so the nitrite is never released into the water to be measured.
My tank has been empty for 6 months, did my bacteria starve?
No. It is almost impossible to starve bacteria. They will adjust their metabolism and reproduction rates based on the food supply. As the amount of available food goes down, they will process it slower and reproduce less. If they go without food long enough they will go into a cystic stage (typically around a year without food). Once food is available again it will take longer for them to recover from this stage but they are still viable.
This does not mean that your tank is ready for fish after sitting dormant for up to a year. Bacteria is part of the food chain and is consumed by many different organisms. Just because your bacteria didn’t starve doesn’t mean it didn’t get eaten or is still viable. Every aquarium will respond differently based on its unique biology.
Why can I add more fish to an older aquarium faster than a new aquarium?
Let’s say you have 2 identical aquariums set up one year apart. They both have the exact same number and size of fish and both have 0 ppm ammonia and nitrite. They must have the same amount of bacteria, right? Well, no. The older tank will have a larger population of bacteria that is processing ammonia at a slower rate. The younger tank will have a smaller population of bacteria with faster metabolisms. If you add new fish to the younger tank you need to wait for the population to increase which can take days. In an older aquarium, the bacteria only need to become more active which can happen in a matter of hours.
JdubC
Community Member
Thanks for the reply Scott. Was thinking some ocean farmed from TBS or something from the LFS. I don’t have an established tank to pull from and don’t have any connections locally yet.
ScottJ
Valuable Member
I hear TBS rock is really good! I would like to get some myself.
JdubC
Community Member
I’ve heard the same. Am even considering putting it in the display as rock island for future corals. Would be in addition to the main dry rock scape.
Cycling a NEW tank? Read this!
What are the basics of a marine aquarium…a Tank, Saltwater, Sand, and Rock.
"Our first saltwater aquarium was a 14-gallon Biocube purchased from a LFS. Being complete newbies, we followed the instructions given by the LFS. Thankfully, they had good advice!
The BioCube was unboxed and assembled, we wiped out dust with vinegar and filled it with saltwater purchased from the store. A 10lb bag of Carbisea Fiji Pink live sand was add to the tank. The LFS sold both cured Fiji rock and Florida live rock. We chose 3 Fiji rocks to cycle the new tank. The Biocube looked spectacular with the sand and rock in place, pump running and lights on a few hours each day. It was a long week, waiting for the tank to mysteriously mature or “cycle” before returning to the store for the next phase.
The LFS said to add life slowly and that a clean-up crew was the way to go. So, 3 blue legged hermit crabs, a few astrea snails and a peppermint shrimp were added to the young tank. Now the tank had some movement with those critters cleaning. This is when we learned about “topping off” for evaporated water. Lids on Biocubes are excellent for slowing evaporation, keeping jumpers in, housing lights, and having a nice clean look. The 2nd week of reef keeping went well.
On the 3rd week a clown fish pair were the next inhabitants followed by learning how to do a water change, again with purchased saltwater. Our reef tank toolkit now included a plastic hydrometer, siphon tube, magnet glass cleaner, pellet food and a net…" -Madelyn & J
The point of sharing about our first marine aquarium is that cycling a new tank can be quite simple and hassle free. Saltwater, live sand, live rock and a stair step approach to adding lifeforms are all that is required. Guess how we cycled the 4,000-gallon holding system?
Saltwater, Live Sand and Real Live Rock.
A simple way to cycle a new tank:
Phase 1-
Add 1lb of live sand and 1lb of live rock per gallon of saltwater (display tank volume) to the new and functioning aquarium. Run lights on a dim setting. Allow the new aquarium to run for 5-7 days before adding anything. During this time, life forms in real live rock & live sand will take care of the biology / chemistry part of cycling. There is no need for additional bacteria products or feeding. If you follow the recipe above, the tank will cycle in one week.
(Depending on the individual pieces of live rock used, you may not see any ammonia during the cycling period.)
Phase 2-
Add more lifeforms but do so gradually as to allow bacteria to multiply. We highly recommend adding a bit more live rock to further boost beneficial microorganisms and add the cleanup crew.
Give the young aquarium another week to further mature.
Phase 3-
Add fish / corals but do so gradually. A tank cycled naturally in this stair step method builds a solid bacterial and micro critter community for a long term, healthy and stable marine environment. Starting a reef tank using this method and keeping a weekly maintenance routine will help you avoid cyano, dinos and hair algae.
It is VITAL to use quality sand and quality real live rock when cycling a tank using this method.
Link to TBS Live Rock
Link to TBS Live Sand
What are the basics of a marine aquarium…a Tank, Saltwater, Sand, and Rock.
"Our first saltwater aquarium was a 14-gallon Biocube purchased from a LFS. Being complete newbies, we followed the instructions given by the LFS. Thankfully, they had good advice!
The BioCube was unboxed and assembled, we wiped out dust with vinegar and filled it with saltwater purchased from the store. A 10lb bag of Carbisea Fiji Pink live sand was add to the tank. The LFS sold both cured Fiji rock and Florida live rock. We chose 3 Fiji rocks to cycle the new tank. The Biocube looked spectacular with the sand and rock in place, pump running and lights on a few hours each day. It was a long week, waiting for the tank to mysteriously mature or “cycle” before returning to the store for the next phase.
The LFS said to add life slowly and that a clean-up crew was the way to go. So, 3 blue legged hermit crabs, a few astrea snails and a peppermint shrimp were added to the young tank. Now the tank had some movement with those critters cleaning. This is when we learned about “topping off” for evaporated water. Lids on Biocubes are excellent for slowing evaporation, keeping jumpers in, housing lights, and having a nice clean look. The 2nd week of reef keeping went well.
On the 3rd week a clown fish pair were the next inhabitants followed by learning how to do a water change, again with purchased saltwater. Our reef tank toolkit now included a plastic hydrometer, siphon tube, magnet glass cleaner, pellet food and a net…" -Madelyn & J
The point of sharing about our first marine aquarium is that cycling a new tank can be quite simple and hassle free. Saltwater, live sand, live rock and a stair step approach to adding lifeforms are all that is required. Guess how we cycled the 4,000-gallon holding system?
Saltwater, Live Sand and Real Live Rock.
A simple way to cycle a new tank:
Phase 1-
Add 1lb of live sand and 1lb of live rock per gallon of saltwater (display tank volume) to the new and functioning aquarium. Run lights on a dim setting. Allow the new aquarium to run for 5-7 days before adding anything. During this time, life forms in real live rock & live sand will take care of the biology / chemistry part of cycling. There is no need for additional bacteria products or feeding. If you follow the recipe above, the tank will cycle in one week.
(Depending on the individual pieces of live rock used, you may not see any ammonia during the cycling period.)
Phase 2-
Add more lifeforms but do so gradually as to allow bacteria to multiply. We highly recommend adding a bit more live rock to further boost beneficial microorganisms and add the cleanup crew.
Give the young aquarium another week to further mature.
Phase 3-
Add fish / corals but do so gradually. A tank cycled naturally in this stair step method builds a solid bacterial and micro critter community for a long term, healthy and stable marine environment. Starting a reef tank using this method and keeping a weekly maintenance routine will help you avoid cyano, dinos and hair algae.
It is VITAL to use quality sand and quality real live rock when cycling a tank using this method.
- Purchase live sand that is sold in water. If it's not TBS Live Sand, then try CaribSea sand. *Remember to use 1lb sand per gallon in the display tank.
- Purchase live rock, REAL live rock. Use real live rock that is either aquacultured in the ocean or has aged in a mature reef aquarium either from a LFS or trusted hobbyist. * Remember to use 1lb rock per gallon in the display tank.
- For Phase 1, choose live rock that is somewhat plain. Avoid large lifeforms on rock such as sponges, corals, macroalgae, etc. that is found on premium rock.
- Dry rock is not live rock. Dry rock soaking in saltwater is not live rock.
- Whether you use live sand and live rock from Tampa Bay Saltwater or from another source, just make sure you buy quality live products…
Link to TBS Live Rock
Link to TBS Live Sand
I know, it’s the number one noob question. What the actual exclamation point has happened to my cycle.
I have read the threads for hours and still can’t answer my question.
Started the tank with dead rock and dead ceramic media (ceramic media was added 48 hours after bottle bac). Followed advice and did not bleach the dead rock/media. Blew it out with an air hose, pressure washed rinsed with RO/DI and dried it in the sun for a week.
Also in the tank: caribsea Fiji pink live sand (did not rinse), Tropic Marin sun-biotic reef salt (contains prebiotic and probiotic bacteria).
set the tank up and let the sand settle for about 48 hours.
Tested parameters for a baseline using both tropic Marin and Red Sea kits. Test showed the presence of small amounts of ammonia (0.5) and nitrites and nitrates. I was told nitites/nitrates were not possible and to add bottle bac. I did. Per instructions I did not add ammonia at the time.
Followed procedure for Dr. Tim’s when the proper day rolled around and ammonia was still at 0.5, I added to 2ppm.
Ammonia finally got down to 1 ppm with nitrites at 10. Nitrates were reading high as well but idk how much of that was one effecting the other. I let it sit a few days ammonia was unchanged but nitrites kept creeping up to the point they were above 40.
I followed Dr. Tim’s instructions and did a partial water change to bring down nitrites. It worked lowering nitrites to 2. It also lowered ammonia to about 0.25. I added ammonia to 2ppm. 24 hours later, ammonia is at .5-.8 depending on the test and nitrites are back up to 10.
According to the Dr. Tim’s schedule I should add to 2 ppm and do a water change to bring down nitrites that read over 5.
I’m a month into a cycle with Dr. Tim’s.
So questions: where are all the nitrites coming from. I know ppl don’t measure them because they probably don’t harm marine fish but Dr Tim says super elevations will stall you out and that does appear to have occurred with ammonia not moving and nitrites soaring for weeks on end. I will reiterate that I did get a dip of at least 1ppm of ammonia in 24 hours after the water change.
Second question: follow the formula of adding to 2 ppm ammonia and just wait for it to clear 2ppm in 24 hours?
Third question: more water changes if nitrites continue to rise?
Current parameters:
Spec gravity 1.025
Phos >0.3
PH 7.8-8 depending on test
Temp 78* F
Filter floss
EDIT: I wonder if the dead rock had enough biomaterial that it is still leaching ammonia from decaying organisms and I’m just stuck until that cycle is under control. Forgot to mention I have had several what I believe to be bacterial blooms on the surface.
Edit again: I retested ammonia tonight so about 48 after I last added 2ppm and was at 0.2 on 3 tests. (The first test showed me back up to 1 ppm and I knew that just could not be possible). So I added 2ppm and fingers crossed it clears out in 24 hours and I can put something in this tank!
I have read the threads for hours and still can’t answer my question.
Started the tank with dead rock and dead ceramic media (ceramic media was added 48 hours after bottle bac). Followed advice and did not bleach the dead rock/media. Blew it out with an air hose, pressure washed rinsed with RO/DI and dried it in the sun for a week.
Also in the tank: caribsea Fiji pink live sand (did not rinse), Tropic Marin sun-biotic reef salt (contains prebiotic and probiotic bacteria).
set the tank up and let the sand settle for about 48 hours.
Tested parameters for a baseline using both tropic Marin and Red Sea kits. Test showed the presence of small amounts of ammonia (0.5) and nitrites and nitrates. I was told nitites/nitrates were not possible and to add bottle bac. I did. Per instructions I did not add ammonia at the time.
Followed procedure for Dr. Tim’s when the proper day rolled around and ammonia was still at 0.5, I added to 2ppm.
Ammonia finally got down to 1 ppm with nitrites at 10. Nitrates were reading high as well but idk how much of that was one effecting the other. I let it sit a few days ammonia was unchanged but nitrites kept creeping up to the point they were above 40.
I followed Dr. Tim’s instructions and did a partial water change to bring down nitrites. It worked lowering nitrites to 2. It also lowered ammonia to about 0.25. I added ammonia to 2ppm. 24 hours later, ammonia is at .5-.8 depending on the test and nitrites are back up to 10.
According to the Dr. Tim’s schedule I should add to 2 ppm and do a water change to bring down nitrites that read over 5.
I’m a month into a cycle with Dr. Tim’s.
So questions: where are all the nitrites coming from. I know ppl don’t measure them because they probably don’t harm marine fish but Dr Tim says super elevations will stall you out and that does appear to have occurred with ammonia not moving and nitrites soaring for weeks on end. I will reiterate that I did get a dip of at least 1ppm of ammonia in 24 hours after the water change.
Second question: follow the formula of adding to 2 ppm ammonia and just wait for it to clear 2ppm in 24 hours?
Third question: more water changes if nitrites continue to rise?
Current parameters:
Spec gravity 1.025
Phos >0.3
PH 7.8-8 depending on test
Temp 78* F
Filter floss
EDIT: I wonder if the dead rock had enough biomaterial that it is still leaching ammonia from decaying organisms and I’m just stuck until that cycle is under control. Forgot to mention I have had several what I believe to be bacterial blooms on the surface.
Edit again: I retested ammonia tonight so about 48 after I last added 2ppm and was at 0.2 on 3 tests. (The first test showed me back up to 1 ppm and I knew that just could not be possible). So I added 2ppm and fingers crossed it clears out in 24 hours and I can put something in this tank!
Last edited:
ScottJ
Valuable Member
What test kits are you using?
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