The cycle of nitrites and nitrates

[danielcassar]

Hi all,

i want some help regards nitrites and nitrates problems.
i have a marine setup which is now only 2 weeks old...so I am waiting for the natural cycle of it. in it i have life rock which i brought it directly from the sea and i use sea water as well.

when i tested sea water the results were these:

• 8.4 pH
• 0 mg/l nitrites (NO2)
• 0 mg/l nitrates (NO3-)

after 1 week i did the tests for my aquarium and the results were these:

• 8.4 pH
• 0.30mg/l nitrites (NO2)
• 80mg/l nitrates (NO3-)

i did some water change because of some debris from the rocks
and the results after 2 weeks are :

• 8.4 pH
• >0.50mg/l nitrites (NO2)
• and over 100mg/l nitrates (NO3-)

which means that its really bad the water condition. i need to know if this is normal during the secret cycle..if yes how long its going to take to settle down...if no what can i do?? and what is wrong?


Thanks
daniel

[Ninong]

Hi all,

i want some help regards nitrites and nitrates problems.
i have a marine setup which is now only 2 weeks old...so I am waiting for the natural cycle of it. in it i have life rock which i brought it directly from the sea and i use sea water as well.

Hello Daniel,

I think the problem you are having is in your "live rock." I assume you collected rock from the Mediterranean near Malta, right? If so, this is not the same as live rock that is collected from coral reefs. The Mediterranean Sea is temperate. It has no coral reefs. True live rock is composed of the skeletal remains of scleractinian corals (hard corals). It can also be aquacultured using older material, such as limestone, that is placed in the sea and allowed to 'mature.'

I don't think the rock from the Mediterranean will work as well in a marine aquarium. Do you have any friends on Malta who have tried this? The problem is that the rock in the Mediterranean is really not permeable and incapable of providing habitat to the beneficial bacteria that are necessary for nitrification and denitrification.

when i tested sea water the results were these:

• 8.4 pH
• 0 mg/l nitrites (NO2)
• 0 mg/l nitrates (NO3-)

after 1 week i did the tests for my aquarium and the results were these:

• 8.4 pH
• 0.30mg/l nitrites (NO2)
• 80mg/l nitrates (NO3-)

i did some water change because of some debris from the rocks
and the results after 2 weeks are :

• 8.4 pH
• >0.50mg/l nitrites (NO2)
• and over 100mg/l nitrates (NO3-)

which means that its really bad the water condition. i need to know if this is normal...

The first results are normal. By the way, did you happen to test the salinity? I'm just curious what the salinity is in the Mediterranean near Malta. I assume it's somewhere near 36-37 ppt but I would love to know what your test results show, assuming you tested it.

...during the secret cycle..if yes how long its going to take to settle down...if no what can i do?? and what is wrong?

The rock you put in your tank is producing the nitrogen right now. This could go on for quite some time. Do you have a sand bed? If so, how deep is it? The sand bed, if it's deep enough, could provide beneficial denitrification benefits but you really need to consider adding some real live rock. I'm not sure how long it will take for your current rock to settle down and stop producing nitrogen. Once it settles down, I guess you could leave some of it in there as base rock but it will never be able to perform the functions we attribute to real live rock.

I would suggest that you consider removing all of the rock you have in there now and replacing it with live rock. I believe live rock from the Red Sea may be available in your area. If so, it may be cheaper than live rock from the Indo-Pacific. Some European hobbyists use articifial ceramic rock with just a small amount of real live rock. The real live rock sort of seeds the artificial live rock. In any case, I don't think the rock you have in there right now is helping matters, assuming you collected it from the Mediterranean.



P.S. -- I'm moving your thread to the Reef Aquariums forum because the forum you posted it in is really just for questions relating to treatment of sick marine fish. If you're setting up a tank strictly for marine fish with no corals or other invertebrates, then I will move you to the Saltwater Fish forum.

[danielcassar]

hi ninong,

before i start to answer your questions i want to share with you my setup and equipment installed..(see pics as well)

• main tank which is 50 gallons (135cm x36cm x 36cm)

In it i have...

• local live rock,
• live sand which is approx 1 inch deep
• power head for circulation approx 1250 l/h

than the water from the main tank overflows by a DIY overflow system to a sump under the main tank. in the sump i have

• bioballs (wet and dry)
• activated carbon
• haqos protein skimmer with a pump of 1850 l/h
• and a pump to bring the water again to the main tank

With this system i have an extra external eheim professional 3 filter with the power of 1250l/h

and soon with a lightning hood of 3 tubes 2 white and actnic blue.

Now regards to your questions here are some answers...
Yes i brought live rock from our sea Malta which is in the Mediterranean.
You told me that rocks are "incapable of providing habitat to the beneficial bacteria that are necessary for nitrification and denitrification.".....Can i add other materials which they can provide habitat for the beneficial bacteria?!....like bioballs and biohome ( :: Tarkus Aqualife - Welcome :: ).

regards to our rocks...maybe im going to ask a stupid question but if the rocks are not good why our sea water is perfect regards to nitrites and nitrates?
regards to salinity it is 1.026 sg (specific gravity).

thanks for your help
daniel

[Ninong]

In it i have...

• local live rock,
• live sand which is approx 1 inch deep
• power head for circulation approx 1250 l/h

You would get better results if you increased the depth of the sand bed to at least 2" (5cm). The sand bed can be a valuable source of denitrification but only if it provides anaerobic conditions.

than the water from the main tank overflows by a DIY overflow system to a sump under the main tank. in the sump i have

• bioballs (wet and dry)
• activated carbon
• haqos protein skimmer with a pump of 1850 l/h
• and a pump to bring the water again to the main tank

A wet/dry trickle filtration system is not in common use anymore in our country for reef aquarium filtration. While it is capable of nitrification, it does a poor job with denitrification because it provides few, if any, anoxic areas.

In truth, once a reef aquarium has a functional amount of live rock and live sand, then that is all the biological filtration it needs. It really doesn't need outside biological filtration such as a trickle filter with bio-balls. However, trickle filters with bio-balls are still quite common on fish-only marine tanks. That is because many of those tanks need extra biological filtration because of the heavy output of waste from the fish.

I assume you are planning a fish-only with live rock system, and, if so, then a trickle filter with bio-balls is one way to do it.

The same comment holds true for the canister filter. Even though they are not used much anymore on reef tanks, they are still common on fish-only marine tanks.

I keep forgetting that I moved your thread to the Reef Aquariums forum without knowing for sure if you plan on setting up a reef tank or a fish-only with live rock tank. If this is going to be a fish-only with live rock tank, then I will move you to Lee's forum for fish-only systems and you can benefit from his many years of experience with such systems.

With this system i have an extra external eheim professional 3 filter with the power of 1250l/h

and soon with a lightning hood of 3 tubes 2 white and actnic blue.

Daniel, the more I read you comments, the more I realize that this is not intended to be a reef aquarium. I believe the lighting you are describing is normal output fluorescent lighting, which is perfectly fine for a fish-only aquarium of this size but not recommended for a reef aquarium.

Therefore, after I finish my reply, I will move you to the Fish-Only forum.

Now regards to your questions here are some answers...

Yes i brought live rock from our sea Malta which is in the Mediterranean.
You told me that rocks are "incapable of providing habitat to the beneficial bacteria that are necessary for nitrification and denitrification.".....

regards to our rocks...maybe im going to ask a stupid question but if the rocks are not good why our sea water is perfect regards to nitrites and nitrates?

Daniel, we can't compare our small home aquariums with the ocean. For one thing, there is the dilution factor. Another thing is we don't have phytoplankton in our water column like the ocean has. And sedimentary denitrification is a significant source in the ocean, especially in shallower waters. Live rock in the ocean, is an insignificant source of denitrification. Most of the nitrogen cycle is completed in the water column in the ocean.

However, the rock in your aquarium looks like it may very well be limestone. And it does look like it has lots and lots of tiny holes and crevices for bacteria to colonize. It looks a lot better than I expected. I was thinking more on the lines of what we might find on the west coast of California.

As I said above, I will now move your thread to Lee's forum for Fish-Only aquariums because I believe that is what you are setting up.

Good luck!

[leebca]

Hi Daniel,

Unfortunately the live rock you have is really not tropical live rock. There will be die-off as the rock 'cures' to the new temperature of tropical. But, you really don't want this. You want tropical live rock, which as Ninong pointed out, you may have access to from the Red Sea.

In addition to your nitrite and nitrate tests, you need to test for ammonia, also.

The short answer to help you with your aquarium is to start over. Trying to get the current rock to work properly is going to create problems later that will be traced back to using rock unsuitable for tropical aquariums.

The rock you have will not likely every be efficient at reducing the nitrate levels. It will do this to some extent, but not the extent of live rock from the proper water.

With enough of the right live rock and a 1 to 2 inches substrate, you'll have a good start to a successful aquarium.

Have you read this post? Setting Up a FOWLR Aquarium

Good luck!

[danielcassar]

hi all

thanks for your recommendations..

regards to ammonia the reading was 0.5 mg after 1 week but after 2 weeks it is lowered down by nearly 0...but nitrites are stilll very high over 50mg/l and even nitrates are high.. how can i lower nitrites?

thanks
daniel

[leebca]

You don't and you don't want to. Let Nature take its course. It cannot be rushed. When there are enough bacteria there to handle the nitrites they will 'suddenly' disappear.

[danielcassar]

ok thanks..
is it a mistake if i do a partial water change or it doesnt effect the cycle?


thanks lee u always helpful

[leebca]

Really not a good idea to do a water change, more than you would routinely do. The nitrites being there will encourage the bacteria to take hold and multiply. During the setup process you'll note that you should start your maintenance routine right away so the system (and you) gets into the groove.

[danielcassar]

Great NEWS!!!! after 1 month of my marine setup...finally my nitrites are getting down and hopefully in 1 week time they will be 0 ..

i noticed that the pH is going down a bit from 8.2 to 7.8...any considerations or suggestions!?

Thanks
daniel

[leebca]

Daniel,

You'll find that pH control is one of the most misunderstood parts of this hobby. Hobbyists think they just need to buy things and put into the aquarium to try and control the pH. But I'll tell you the secret to pH control: controlling the buffering ability of the water.

The buffering ability of the water is what controls the pH. What is the buffering ability? It is made up of alkalinity, calcium, and magnesium. Please read through this post and you'll find the section about these three items: What is Water Quality. So the fact that your pH is 'off' means these three parts of the buffering ability of the water are 'off.'

They need to be kept in balance. Once in balance, the pH will take care of itself. I hope where you live you can obtain test kits for these, and be able to make the adjustments. Just follow the guidelines in that post. Make no additions until you can measure the results and know what is needed to do.

Good luck!

[danielcassar]

thanks lee...your posts are always helpful

thanks
daniel