Using Nitrite and Nitrate level to gauge cycling of tank

[Ralph]

Hi,

Some weeks ago, I started a new tank and looking at the test kits for ammonia(NH3), nitrite(NO2) and nitrte (NO3), I was surprised to find out how expensive they are.Easily more than $40-50 if I were to get the complete sets individually. Anyway, East Ocean recommended me this particular litmus kit which allows me to test NO2 and NO3. The JBL EasyTEst 6-in-1.

So logic goes is, ammonia will be produced, and then the beneficial bacteria will concert ammonia to nitrite. So when there is nitrite, means there is beneficial bacteria for this stage. The next stage will then be from nitrite to nitrate, and when the nitrate is present, It means that there are bacteria for this second stage and the cycling is completed.

So, I tested my water just a week ago, there was nothing on both NO2 and NO3 yet, but today, there is zero trace of NO2 but has 10mg/l of NO3 already.

Can I take this to be an indication that my tank is completely cycled?

There cannot be any NO3 if there were no NO2 to start with sod if NO3 is present with NO2 is missing, it would mean my tank is cycled?

[Urban Aquaria]

The bacteria that convert ammonia (NH3) to nitrite (NO2) and the bacteria that convert nitrite (NO2) to nitrate (NO3) are made up of different species, and they grow and work at different speeds.

Its possible to see nitrite at zero, while nitrate shows readings, this is usually because one bacteria type happen to be more established or working faster than the other... its like a factory production line, if the worker in front is slower and the worker in the middle is faster, then the worker in the middle finish his job earlier and then look like he has not much work to do.

Does your test kit measure ammonia (NH3)? Because there may still be ammonia in the water column that is still yet to be processed. The tank is only considered cycled if both ammonia and nitrite stay consistently at zero, and only nitrate show readings (this has to be stable for at least a few days to be safe, not just a temporary cycle).

Btw, paper strip tests tend to be less accurate and display wider variations than liquid test kits, so do take the measurements as rough estimates, as the actual readings may be different.

[Ralph]

UA,

Thanks for enlightenment. Thats a very good point. I am missing the ammonia kit. Will get one just to do full check.

[Ralph]

I tested the ammonia level using API kit yesterday and found 0.5ppm. Seems like my cycling has only just begun.

But for sure there is some small beneficial bacteria on the bio-media of the filter.

By the way, as I am using the Fluval Spec V's Stock filter, I highly suspect that this will not be enough for my bio-load even though I am not keeping alot of fishes.

But if I was to add on more bio-media on top of my existing one, will it affect any of my cycling?

I don't think it will, the existing BB will still grow and addition bio-media will just catch up thereafter, but I like to seek brother's opinions on this.

The bacteria that convert ammonia (NH3) to nitrite (NO2) and the bacteria that convert nitrite (NO2) to nitrate (NO3) are made up of different species, and they grow and work at different speeds.

Its possible to see nitrite at zero, while nitrate shows readings, this is usually because one bacteria type happen to be more established or working faster than the other... its like a factory production line, if the worker in front is slower and the worker in the middle is faster, then the worker in the middle finish his job earlier and then look like he has not much work to do.

Does your test kit measure ammonia (NH3)? Because there may still be ammonia in the water column that is still yet to be processed. The tank is only considered cycled if both ammonia and nitrite stay consistently at zero, and only nitrate show readings (this has to be stable for at least a few days to be safe, not just a temporary cycle).

Btw, paper strip tests tend to be less accurate and display wider variations than liquid test kits, so do take the measurements as rough estimates, as the actual readings may be different.

[Bieffe]

Yes quite true with the media but how much more can go in? Few pieces? Then next issue us flow rate. Too much media will slow down the exchange. So even if u have lots of media the water is only renewed at same rate. So will come a point the system cannot sustain the livestock. No choice but to reduce. Like my case tank same...but canister is getting bigger.

[Ralph]

I am actually contemplating adding a more "powerful" bio-chem stuff like Seachem Purigen. Create a slot or revamp the current sponge layout to insert this .

Anyone with experience in this product?

Yes quite true with the media but how much more can go in? Few pieces? Then next issue us flow rate. Too much media will slow down the exchange. So even if u have lots of media the water is only renewed at same rate. So will come a point the system cannot sustain the livestock. No choice but to reduce. Like my case tank same...but canister is getting bigger.

[Urban Aquaria]

I am actually contemplating adding a more "powerful" bio-chem stuff like Seachem Purigen. Create a slot or revamp the current sponge layout to insert this .

Anyone with experience in this product?

I use Seachem Purigen in some of my tanks (especially the ones with higher bio-loads), it does help to remove excess organic compounds and waste that contribute to ammonia. Purigen has a limited lifespan though and needs to be re-charged regularly.

Note that you should use Purigen only after the tank is fully cycled, make sure the beneficial bacteria population is established and strong beforehand.... if you add Purigen while the tank is cycling, it'll will tend to remove the "food" that the beneficial bacteria need to consume to grow properly, hence extend the cycling period and may result in a weaker bacteria population.

[Ralph]

Hi UA,

Thanks once again for sharing your knowledge! Much grateful!

I use Seachem Purigen in some of my tanks (especially the ones with higher bio-loads), it does help to remove excess organic compounds and waste that contribute to ammonia. Purigen has a limited lifespan though and needs to be re-charged regularly.

Note that you should use Purigen only after the tank is fully cycled, make sure the beneficial bacteria population is established and strong beforehand.... if you add Purigen while the tank is cycling, it'll will tend to remove the "food" that the beneficial bacteria need to consume to grow properly, hence extend the cycling period and may result in a weaker bacteria population.

[Ralph]

By the way, since we are on this, what about "Miracle Mud"? It seems to have the same function as Purigen but don't need to be in the filter, can just place it as a substrate somewhere in the tank.

I use Seachem Purigen in some of my tanks (especially the ones with higher bio-loads), it does help to remove excess organic compounds and waste that contribute to ammonia. Purigen has a limited lifespan though and needs to be re-charged regularly.

Note that you should use Purigen only after the tank is fully cycled, make sure the beneficial bacteria population is established and strong beforehand.... if you add Purigen while the tank is cycling, it'll will tend to remove the "food" that the beneficial bacteria need to consume to grow properly, hence extend the cycling period and may result in a weaker bacteria population.

[Urban Aquaria]

By the way, since we are on this, what about "Miracle Mud"? It seems to have the same function as Purigen but don't need to be in the filter, can just place it as a substrate somewhere in the tank.

I googled it and seems it's meant for use in saltwater reef tanks (since reef tanks don't usually use soil), sort of like a "soil-like" substrate for reef systems.... not sure how it can be beneficial for freshwater planted tanks though, since most planted tanks already use active soil substrate which does the same job of housing anaerobic beneficial bacteria, along with supplying nutrients.

Its not the same as Purigen though, its doesn't physically absorb and store the organic compounds for separate chemical removal.