Help with Nitrates

[Natural Blue]

Little back story, 120 gallon tank with 40 gallon sump. We have been cycling 100+lbs of live rock and 80lbs of sand for 4 1/2 weeks in the DT with our protein skimmer hung on the side of the DT. I was waiting on a few things before getting the sump online.

Ammonia, Nitrites, Nitrates, were all 0ppm.

Nitrates just jumped up the last week and half and steadily climbed to 160ppm. I turned the sump on two days ago, added 45 gallons on new saltwater, and also added a 7" sock for the drain lines. After this nitrates dropped down to about 50ppm.

Do I just wait for the skimmer and sock and the sump to keep filtering and lowering nitrates? I could do a huge water change but then wouldn't I be getting rid of all the water I just cycled for 4 1/2 weeks?

Really confused on this one, and was hoping to have fish by Christmas.

[fishgate]

Once your tank is cycled, the water is largely irrelevant. You could at that point do a 90% change and it should not affect your levels. clarification: I mean it will affect what is in the water when you change it, but your tank will still be cycled.

I'd wait another few weeks for things to stabilize with everything running. I assume you are using RO water.

[Natural Blue]

Originally Posted by fishgate

Once your tank is cycled, the water is largely irrelevant. You could at that point do a 90% change and it should not affect your levels. clarification: I mean it will affect what is in the water when you change it, but your tank will still be cycled.

I'd wait another few weeks for things to stabilize with everything running. I assume you are using RO water.

Yes all top off water is RO I got from the LFS. Will adding
the sock to the drains do much at all to lower Nitrates?

[jdm01]

I would make sure the skimmer is running. I have typically tried to do 10% water changes each week. It has worked for me in my other tank. My 65G has not been up for a week yet. When it has been a week I will do a 10% water change. That is just me.

[Natural Blue]

Skimmer is running, its been running the entire time.

[MrTuskfish]

Originally Posted by fishgate

Once your tank is cycled, the water is largely irrelevant. You could at that point do a 90% change and it should not affect your levels. clarification: I mean it will affect what is in the water when you change it, but your tank will still be cycled.

I'd wait another few weeks for things to stabilize with everything running. I assume you are using RO water.

Yeah, the bacteria that keeps a tank cycled lives in the LR, substrate, filter media, etc., not the water column. With that 160 reading; I'd almost expect a bad test, or bad test kit. Nitrate test kits can be very unreliable. If you get a jump like this, re-test.

[Carey1465]

Do you have any bio balls in the sump? I had high nitrates but no higher than 80. So I did alot of researching and decided to take the bio balls out SLOWLY and replace them with live rock. I also added 1" of sand to my sandbed and kept adding more live rock. I went from 80's down to 10's within 3 months or so. How deep is your sandbed?

Do you have a clean up crew? Any hermit crabs and such? That sock filter will hold alot of detritus and will probably need to be cleaned every 2-4 days. Is there any detritus at the bottom of your sump? One more question. What kind of skimmer do you have?

[daplatapus]

If I understand the nitrogen cycle properly, unless you have a deep sand bed that gives you a hypoxic area for bacteria to convert the nitrates to nitrogen, the only way to get rid of your nitrates is by water changes. And you must get rid of the nitrates built up in your tank. Keep in mind that if you have nitrates, that this is the end result of the nitrogen cycle if you don't have a DSB. This is a good thing. It means you have cultivated tons of bacteria that has turned your ammonia into nitrite and then more bacteria to turn nitrite into nitrate. Do some moderate water changes and keep feeding the tank. The last thing you want is all that beneficial bacteria starving to death and the cycle stalling. So if you do some water changes and are able to drop the nitrate levels, and are able to keep feeding the tank and you don't see an ammonia spike, just more nitrate, you're ready to start adding live stock, your tank has cycled. Just keep an eye on those levels (ammonia, nitrite, nitrate) and regularly change your water as the nitrate levels rise.

[cdineen0823]

I thought have a refugium w/ macro algea helped with nitrate removal? I'm a noob so be gentle.

[boatguy]

Your refugium will help. Anything that consumes nitrates (macro,mangroves, stuff you need to clean off glass) will lower your levels. The trick is to remove the growth from refugium/tank. Also remember to change/clean that filter sock before it becomes a nitrate factory.

[MrTuskfish]

All of the above are good helpers; but LR made nitrate control possible and its deep, porous structure is still the key to nitrate control.

[Natural Blue]

We tested our water at the LFS and between 3 different tests the Nitrates were at 80PPM. We add some carbon in a filter bag yesterday as well as some Purigen.

Sand bed in the tank is about 2" deep. I have sand in my fuge with a couple of LR's and some chaeto, with a light on it 24/7.

The skimmer is a Coralife 125 Super Skimmer and quite frankly I'm having a hard time dialing it in. It either bubbles up all day long never spilling over into the collection cup or it's overflowing into the collection cup. Can't seem to find a happy medium, but maybe that's because there is no livestock?

We add some carbon in a filter bag yesterday as well as some purigen and the Nitrates were at 50ppm this morning. I'm going to test again before going to bed.

There is no CUC in the tank, just sand and rock.

How often do you change the drain sock? Every couple of days seems a bit much but I'm new at this so I have no idea.

[Danzig]

If you have just started using your skimmer that may be the problem. They need a 1-2 week break in period.

[Natural Blue]

Originally Posted by Danzig

If you have just started using your skimmer that may be the problem. They need a 1-2 week break in period.

The skimmer has been on and running for about 5 weeks now.

[MrTuskfish]

Originally Posted by Natural Blue

We tested our water at the LFS and between 3 different tests the Nitrates were at 80PPM. We add some carbon in a filter bag yesterday as well as some Purigen.

Sand bed in the tank is about 2" deep. I have sand in my fuge with a couple of LR's and some chaeto, with a light on it 24/7.

The skimmer is a Coralife 125 Super Skimmer and quite frankly I'm having a hard time dialing it in. It either bubbles up all day long never spilling over into the collection cup or it's overflowing into the collection cup. Can't seem to find a happy medium, but maybe that's because there is no livestock?

We add some carbon in a filter bag yesterday as well as some purigen and the Nitrates were at 50ppm this morning. I'm going to test again before going to bed.

There is no CUC in the tank, just sand and rock.

How often do you change the drain sock? Every couple of days seems a bit much but I'm new at this so I have no idea.

Carbon and Purigen do about the same thing. Neither will do much to reduce nitrates; they're basically water polishers. If your nitrates dropped 30 ppm overnight, something in your testing is off. Only a big WC can do this.

[Natural Blue]

Originally Posted by MrTuskfish

Carbon and Purigen do about the same thing. Neither will do much to reduce nitrates; they're basically water polishers. If your nitrates dropped 30 ppm overnight, something in your testing is off. Only a big WC can do this.

Honestly, it's probably still 80 ppm. Half my problem is I'm having a hard time determining how bad it is with the test kit we have. The nitrates are red on the test kit and the red shades on the kit for 40ppm and 80ppm are so close in color it's hard for me to tell. Think I'm just getting hopeful and sayng it's about 50ppm when it's really still 80ppm.

I guess I'll have to do a 40-50gallon water change tomorrow because we are really wanting fish when everyone comes over for Christmas Saturday.

I'll do some searching but what are moderate Nitrate levels for saltwater fish. Like if the test kit says 5ppm do I need to immediately do a water change or should it be around 10-20ppm. I know the goal is 0ppm all the time but at what point does it become lethal to the livestock.

[MrTuskfish]

Nitrate at 50, even 80 ppm will not hurt fish. Inverts, yes, but nitrate isn't toxic to fish. Fish have been shown to live in water with nitrates in the 100s, even 1000s ppm with no ill effects. (From Bob Fenner;s 'The conscience Marine Aquarist") Personally, I consider 80 an upper limit and there are anecdotal reports of some fish not handling nitrates well. Just for the fun of it, test your LFS water. Unless the fish are on the same central system as inverts (doubtful), I'll bet nitrates exceed 100ppm.

Nitrates aside, rushing fish into a tank that isn't positively cycled can be a big problem. Rushing to add fish without a proper QT regimen is a big risk, IMO & IME. Also, fish should be added slowly, I hope you're not going to try to fully stock this tank in 6 days.

[Natural Blue]

Originally Posted by MrTuskfish

Nitrate at 50, even 80 ppm will not hurt fish. Inverts, yes, but nitrate isn't toxic to fish. Fish have been shown to live in water with nitrates in the 100s, even 1000s ppm with no ill effects. (From Bob Fenner;s 'The conscience Marine Aquarist") Personally, I consider 80 an upper limit and there are anecdotal reports of some fish not handling nitrates well. Just for the fun of it, test your LFS water. Unless the fish are on the same central system as inverts (doubtful), I'll bet nitrates exceed 100ppm.

Nitrates aside, rushing fish into a tank that isn't positively cycled can be a big problem. Rushing to add fish without a proper QT regimen is a big risk, IMO & IME. Also, fish should be added slowly, I hope you're not going to try to fully stock this tank in 6 days.

Definitely not trying to fully stock the tank, but it would be nice to have maybe two clowns and part of a CUC.

The more searching and reading I do today makes me think the new Coralife SS125 is part of the problem. It's barely getting any skimate and from reading it sounds like it's a pretty shoty piece of equipment. I may need to upgrade to a skimmer that works.

[Natural Blue]

Also, can anyone comment on how often the drain sock should be changed.

If I've got a 120 gallon tank and my Nitrates are still at 80ppm, what would be the recommended water change amount?

[MrTuskfish]

At this point, if I follow correctly, you shouldn't have anything to skim. Unless you had a lot of substrate & LR dieoff; your nitrate readings can't possibly be correct. Nitrate comes from decomposing organic material and builds over time. Skimming is a long-term process and shouldn't be needed at all in a newly set up tank with no life. If ammonia and nitrite didn't rise, nitrates couldn't have gone that high, that quickly. Something is just not right with what you're seeing. Nitrate test kits can be very unreliable, but if you've used two kits, who knows. In any case, if you've decided not to QT and don't have any ammonia or nitrite----clownfish are no problem.

[MrTuskfish]

Originally Posted by Natural Blue

Also, can anyone comment on how often the drain sock should be changed.

If I've got a 120 gallon tank and my Nitrates are still at 80ppm, what would be the recommended water change amount?

If you insist. Change 20%. If nitrates don't drop by nearly 20%.....something is out of whack. I still think you're going nuts trying to fix something that ain't broken. Did you have any life in this tank that could have died? What organic source (dead shrimp, live fish, etc. ) did you cycle the tank with?

As to the drain sock: is it filling with crud? If so, what's the source?

[Natural Blue]

Originally Posted by MrTuskfish

At this point, if I follow correctly, you shouldn't have anything to skim. Unless you had a lot of substrate & LR dieoff; your nitrate readings can't possibly be correct. Nitrate comes from decomposing organic material and builds over time. Skimming is a long-term process and shouldn't be needed at all in a newly set up tank with no life. If ammonia and nitrite didn't rise, nitrates couldn't have gone that high, that quickly. Something is just not right with what you're seeing. Nitrate test kits can be very unreliable, but if you've used two kits, who knows. In any case, if you've decided not to QT and don't have any ammonia or nitrite----clownfish are no problem.

It's possible I missed the ammonia spike. We added a shrimp during the cycling period and that thing just disappeared. I didn't test for 2 days so maybe I missed it. That said, even now ammonia and nitrites are still 0ppm, but the Nitrates went up, confirmed with 3 tests now.

[MuffsAbby]

Based on your posts, I too have a hard time understanding where the nitrates are coming from. The only things I can think of are (a) your source water contains nitrate or (b) your test kit is off. If you're about to do a water change, you presumably have water at the ready. Perhaps try testing it. If it shows nitrates, then either your test kit is unreliable or your source water is.

[Natural Blue]

Could the nitrates be because we're not completely cycled or from the shrimp we added weeks ago?

Just tested everything to rule anything out. I have a jug of LFS RO/DI and Saltwater

Tank:
Ammonia - 0ppm
Nitrites - 0ppm
Nitrates- 80ppm
PH - 8.1

Nitrates in Water Sources:
LFS RODI - 0ppm
LFS Saltwater - 0ppm
House filtered tap water used to clean test tubes - 0ppm

[MuffsAbby]

I would find it unusual that a single shrimp could cause nitrates to rise to such a high level. I used a shrimp to cycle my QT, which only has a simple HOB filter, and I never saw nitrates above 20. My QT is only 20g, so levels would be much more concentrated than in your 120g.