Need advice on N-cycle

[conoyo]

Dear Bros,

Seeking advice about N-Cycle, i just start a new tank and it has been running for 7 days. I am not sure whether n-cycle staring or not.

Day 1 setup, everything's fine, tank set at 25 degree, skimmer on, refugium on 7x24, with some Algae in the refugium

Day 2, the tank start to appear some brown algae but not bloom

Day 3, added 5 small (about 1/2 ~ 1 inch) clown fish and a Ricordea Yuma

Day 4, added 3 small zoa frag

Day 5, added Seachem matrix 1 liter, denitrate 1 liter, and active carbon

Day 6, set timer for refugium light to be switch on from 19:00 to 08:00, chiller set to 26 degree

Day 7 which is today.

Test NO3 every day. Day 1 is 0, Day 2 is 12.5 and Days 3 onward till today is between 12.5 to 25.

Fishes and coral all looks good. brown algae start to grow on artificial live rock

Tank size: 30" x 18" x 18", main tank about 150 liter water, refugium about 30 liter.

Over-sized skimmer: for 1000 liter (plan to do a sps tank)

Just 2 small piece live rock in refugium, and using artificial live rock on main tank.

Caribsea Livesand

I am wondering whether the n-cycle finished yet. Should i change some water now?

[mitchell.liang.9]

Have u checked for ammonia and nitrite?? If they are both 0 than the cycle is most probably done. Usually cycling should be done without adding livestock to prevent likelihood of livestock dieing. So keep an eye on them. All the best!

[Edmund Koh]

Bro,

Growth of algae doesn't really represent anything on the N-cycle. All it shows is that there are Nitrates present in your tank.

The product of a proper N-cycle should be beneficial bacteria growth among your rocks and other bio-filter media in your sump. In a complete cycle, we will be looking at the growth of 3 different types of bacteria, the first being responsible for using up the Ammonia released into the tank (either through a decomposing market prawn, decomposition of excess fish food or through fish waste) and converting it into Nitrite. The second would be responsible of using up the Nitrite produced by the first group of bacteria and converting it into Nitrate. The third group of bacteria would be responsible of converting this Nitrate into Nitrogen gas.

Both Ammonia and Nitrite are poisonous to our fishes and thus the first 2 groups of bacteria are the most important. Nitrate on the other hand is only harmful in large numbers and can be effectively removed from the tank through the skimmer or through growth of algae. Thus the last group of bacteria may not be so important.

Do refer to the graph below for how the N-cycle should work.

As you can see from the graph, proper cycling should take about 40-60 days.

Because this process start with a spike in Ammonia followed by a spike in Nitrite, Live stock should not be present in the tank as these chemicals are deadly and we wouldn't be fair to the fishes and corals.

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What is happening in your tank at the moment would be called Live Fish Cycling Process where we use Fish waste as the source of the ammonia spike which would kick start the cycling process.

To know if the N-cycle has started, you would need to start checking for the ammonia readings in your tank.

Honestly, I doubt your clownfishes would survive this ammonia spike and even if it does, it wouldn't survive the Nitrite spike. To be fair to your clownfishes and other livestock, do try and find it a new home or a kind bro here who is willing to hold onto them until your tank cycles.

During the N-cycle, do keep your tank fishless and turn off your skimmer and chiller to speed up the process of bacteria growth. In the mean time, do take readings of your Ammonia, Nitrite and Nitrate on a weekly basis to know where you are currently in the N-cycle.

[conoyo]

Haven't bought tester for ammonia and nitrite. Only bought NO3, Calc, Mg, PO4 tester. Will buy ammonia and nitrite tester after work today.

Coral and fishes in tank looks ok till today. Doesn't look like there is any sign of ammonia / nitrite.

[asg]

Bad move to add in LS so soon ah. Once your coral starts to die off, your water parameters will swing more and you wont be able to tell what is the cause... plus very soon you will need to fight itch liao.

Your LS is appearing fine (for now) only because your water is new, not because your bio filter is ready to handle them.

Harsh word, but keeping new fish alive and healthy is not given, even to old bird loh.

[conoyo]

Bad move to add in LS so soon ah. Once your coral starts to die off, your water parameters will swing more and you wont be able to tell what is the cause... plus very soon you will need to fight itch liao.

Your LS is appearing fine (for now) only because your water is new, not because your bio filter is ready to handle them.

Harsh word, but keeping new fish alive and healthy is not given, even to old bird loh.

Thank you, will keep an eye on it and test ammonia and NO2, will get some mixed salt water ready to change.

[asg]

Thank you, will keep an eye on it and test ammonia and NO2, will get some mixed salt water ready to change.

Sure bro. You might also want to consider dosing bateria to speed thing up and to reduce NO3.

[SubzeroLT]

This is an excellent chart.

Not seen something like this before.

Do refer to the graph below for how the N-cycle should work.

[conoyo]

Sorry another question, Does N-Cycle up to NO3 generation or denitrification?

[Edmund Koh]

Sure bro. You might also want to consider dosing bateria to speed thing up and to reduce NO3.

I do agree with this. This is to make up for bacteria that have been skimmed up by your skimmer and also to over come the increased bioload.

You can also consider adding a biopellets reactor with biopellets to boost your bio-filtration capabilities.

[Edmund Koh]

Sorry another question, Does N-Cycle up to NO3 generation or denitrification?

An Ideal cycle would end with denitrification, however not every tank is capable of cultivating denitrifying bacteria a this group of bacteria requires a Anaerobic (lack of oxygen) setting like deep sand bed or big live rocks or bio media (only those with anaerobic properties).

For tanks that are not capable of cultivating enough denitrifying bacteria, a good skimmer will do the job of removing NO3 from the system. Macro algae will also do the same job of removing NO3. So its safe to end the N-cycle at the generation of NO3 as long as your equipment is able to keep NO3 to a low level and not let it spike too high.

[conoyo]

An Ideal cycle would end with denitrification, however not every tank is capable of cultivating denitrifying bacteria a this group of bacteria requires a Anaerobic (lack of oxygen) setting like deep sand bed or big live rocks or bio media (only those with anaerobic properties).

For tanks that are not capable of cultivating enough denitrifying bacteria, a good skimmer will do the job of removing NO3 from the system. Macro algae will also do the same job of removing NO3. So its safe to end the N-cycle at the generation of NO3 as long as your equipment is able to keep NO3 to a low level and not let it spike too high.

Thank you for the information. Have put 1 liter seachem matrix for cultivating anaerobic bacteria, plan to put another 2 liters for it since my tank doesn't have a lot of space for live rocks.

[Edmund Koh]

Patience is key bro

[asg]

An Ideal cycle would end with denitrification, however not every tank is capable of cultivating denitrifying bacteria a this group of bacteria requires a Anaerobic (lack of oxygen) setting like deep sand bed or big live rocks or bio media (only those with anaerobic properties).

For tanks that are not capable of cultivating enough denitrifying bacteria, a good skimmer will do the job of removing NO3 from the system. Macro algae will also do the same job of removing NO3. So its safe to end the N-cycle at the generation of NO3 as long as your equipment is able to keep NO3 to a low level and not let it spike too high.

well said. But just to add on, protein skimmer does not remove NO3, they just physically remove organic waste from the water before they kanna denitrify to become NO3.

[Edmund Koh]

Haha whoops! My bad on the wrong info. >.<

[conoyo]

Tested Nitrite is zero (Salifert).

Cannot get Ammonia Tester.

[conoyo]

Test again with Salifert Nitrate tester, it is between 2 and 5. Low range is 25-50 which is between 2.5 and 5.0.

Skimmer is 5 times+ of water volume, maybe that contribute.

Have u checked for ammonia and nitrite?? If they are both 0 than the cycle is most probably done. Usually cycling should be done without adding livestock to prevent likelihood of livestock dieing. So keep an eye on them. All the best!

I guess Mitchell is correct since no dead organism from live rock, not much source of ammonia. Will slow down a bit and keep an eye on it.

Thanks Bros.

[Edmund Koh]

Try to get hold of an ammonia test kit and test it at least once every 2 days.

Fish wise I read somewhere about adding 1 inch of fish size every week. So if u want to add a 2-3 inch sized fish then got to wait 2-3 weeks for your next addition. This is to allow got the bacteria in your tank to grow to adapt to the new bioload.

looking forward to another successful tank

[conoyo]

Thank you. Still a bit strange, NO2 still zero and NO3 is 2.5 but lots of brown algae now. Wait for silicate to be consumed before next step.

[Shadow Walker]

Any updates bro? Is the ammonia and nitrite zerolised?

[conoyo]

no sign of ammonia, no2 zero and no3 also zero (Tested no2 and no3 with salifert) other parameters also looks good. SPS frags start growing.

[waterperson]

Bro,

dun mind me budge in on the your topic. I'm newbie in reef as well and just finished cycled my tank. It's a gradual 2 weeks ammonia build-up then sudden zero reading. Same for nitrite and nitrate.

You dun seem to have the same experience of a built up of ammonia n nitrite, it could be because of your live rock and activated carbon. I believe your tank is experiencing a series of "small" nitrogen cycles.

Not sure if a big cycle or small cycles are better, but in your case, your livestock will definitely survive better with smaller ones. With weekly water changes, i believe your tank will achieve the same state as a mature reef tank.

Happy reefing

[conoyo]

Thank you for everyone contribute to the post. Advices from everyone really helpful

I think until now the N-Cycle is finished, there is a diatom bloom 10 days after the tank setup and diatom getting less after few days.

Looks a bit strange to me too because the other tank setup few years ago get normal N-Cycle. This is my first time get N-Cycle finish so quick.

I guess here is the conclusion, please correct me if anything wrong:

1) Use artificial live coral, less dead organism to generate ammonia

2) Live sand come with beneficial ammonifying / nitrifying bacteria

3) Active Carbon, De-Nitrate, Macro-Algae absorb ammonia, nitrite and nitrate.

4) Oversize skimmer removed DOC which help to minimize source of ammonia/nitrite.

Here is the update of my tank, so far haven't change water since trying triton method. Most water parameters looks great, except KH but still in acceptable level.

Water parameter

NO3: 0.0

PO4: 0.0

KH : 7.7

Ca: 480

Mg: 1500

Salinity: 1.025

pH: 8.06 - 8.18

How it looks now All frags look really good but need time to develop a larger colony.

Thanks everyone again. Happy reefing.

[tofubox]

Your assumptions are right. Alot of times where people experience long N cycle is mainly due to the large amount of decaying matter. Would recommend u to stock fishes slowly as bacteria is still unstable due to quick cycle.

[waterperson]

+1 to comments above.

Your scape looks sharp. Pls update the growth whenever u can.