Blargity Flargety!

[SuperXdude]

Dudes (and Dudettes),

I'm completely stumped. I've had an apparent nitrate problem for some time according to my test kit. I've checked the test kit and it's good on tw other tanks. (High on one, and low on another). I did a 25 gal water change last night, and nitrates were still through the roof.

Tank is 80 Euro bowfront, 13 gal sump (tidepool), with 90lb live rock.
Lighting is VHO 48 inch, 10k & Actintic, plus two 12k 175 MH bulbs.

VHO are on for about 10 hours a day, MH are on for about 6 hours.

Ammonia is 0, PH is 8.2, Alk (DkH is "normal" range, as my test kit reads low, normal, high)

I have a yellow tang, scopas tang, cowfish, and a tomato clown. All are fine. No signs of stress.

Also in the tank is a LTA, Green star poylps, an un-id'd species of polyps, and some galaxia. All are doing fine, but the galaxia seems to be receiding just a tad.

I'm going to bring water samples to Alamo and T^2 tomorrow and have them test it as well. I top as well with RO water. I've tested the water before adding and it's nitrate free.

One more thing, my sump is a tidepool style and I just removed the bio-wheel. I was told today it could possibly be a nitrate factory.

Any ideas would be greatly appriciated.

Thanks!

SuperXdude

[JimD]

The bio-wheels can definately be a source of the escalated nitrates, keep an eye on your test results over the next few days for sure... Also, detritus build up especially behind and under rocks can contribute to higher than normal nitrate levels, make sure the flow in these areas is sufficiant..

[Ram_Puppy]

hey, quick point (you probably allready know) but your cowfish is one of those 'caution watch me closely with your corals/anemones' fish... they also release a toxin when they are stressed, or when they die.Are you running any carbon in your tank?

[astrong]

So, what are your nitrates?

Also what additives are you putting in?
Was the LR cured or uncured when you added it?
How often do you feed? How much?

I wouldn't worry about your biowheel, its no more a "nitrate factory" than your sand or live rock. It may be superfluous, but its not detrimental. Nitrates come from organic decomposition, so the more you feed, the higher your nitrates. The more water changes you do the lower your nitrates. Usually you just need to balance these out.

The reason I asked about additives is because some supplements are known to give false results. And getting your results double checked is a good idea, kits can go bad, and some always were...

[GaryP]

Hey X,

A couple of things I thought of after I talked to you at the meeting.

1. Feeding less is not the answer. Actually feeding more often with smaller amounts would be better for your fish. Make sure not a lot hits the bottom. If it does, you want some detritivores to clean it up.

2. Yes, a biowheel produces nitrates, but so does live rock and a lot of everything. The problem isn't that the biowheel (or bioballs for that matter) are producing nitrates. Nitrate production is just part of the nitrogen cycle. The problem is that you don't have the critter to take the nitrate and work it through the rest of the way in the nitrogen cycle.

3. You didn't mention a sand bed in your tank. I somehow think that might be the culprit in your case. Without knowing more about your tank its just a guess.

Nitrogen Cycle:

Organic nitrogen ---> ammonia ---> nitrate ----> nitrite --->
!nitrogen & nitrous oxide gas

Different bacteria complete different stages of this cycle. The final step usually occurs in a deep sand bed or similar anoxic (low oxygen) area of the system. The shallow parts of a sand bed are also very efficient areas for several of the early steps as well as well as live rock. Another possible solution might be adding a refugium. Macroalgae in a fuge would remove the nitrogen at the ammonia and nitrate stages.

If over feeding was truly the problem, I would think you would have a algae bloom as well. This would be result of high phosphates and nitrates.

I would also take a good look at your protein skimmer to make sure it is working efficiently. It might be a good idea to run some vinegar through your skimmer to make sure your vacuum eductor isn't scaled up as well as tearing the pump down and soaking it in vinegar.

Gary

[SuperXdude]

I do have a sand bed...not "deep" but 2-3 inches in places, and i planon adding more sand this month. I do have Southdown on hand, but will try to purchase 40-60 lbs of good live sand instead. Southdown seems to create sandstorms when my fish kick up their fins on occasion. (Tang superiority complex)


SuperXdude

[GaryP]

To get the anoxic conditions needed for denitirfication you need at least 4-6" of sand.

Gary

[matt]

I wouldn't worry about your biowheel, its no more a "nitrate factory" than your sand or live rock. It may be superfluous, but its not detrimental.


This is not entirely accurate. Deep sand beds well populated with micro-fauna will provide habitat for bacteria that processes nitrate into free nitrogen, which then bubbles out of the tank. The bio-wheel does not do that. You're correct in saying that the bio-wheel does not produce nitrates, but it is ineffective at processing them, while a healthy sand bed, and to a certain extent good quality live rock, will process nitrates out of the system. As Gary said, these strains of bacteria require areas of lower O2 content. (meaning within the sand and in porous areas of the rock)

You'll probably never keep up with nitrate production solely by water changes in a stocked reef tank. You need either A) a good skimmer, B) a refugium stocked with caulerpa or some nitrate-consuming algae, C) a healthy sand bed, 4" or so deep, or, best, a combination of these things.

Enjoy.... :D

[NaCl_H2O]

Organic nitrogen ---> ammonia ---> nitrate ----> nitrite --->

I think it is:
Organic nitrogen ---> ammonia ---> nitrite ---> nitrate --->

I remember the order because it all happens at the "rite rate"

[GaryP]

Steve, thanks for the correction, you are correct. What can I say? I had a momentary case of cerebral flatulence. In this case it really doesn't matter. If the nitrogen cycle is stopped at any point there is going to be a buildup of "bad stuff." I think that's the technical term for it anyway.

Gary

[NaCl_H2O]

Steve, thanks for the correction, you are correct. What can I say? I had a momentary case of cerebral flatulence. In this case it really doesn't matter. If the nitrogen cycle is stopped at any point there is going to be a buildup of "bad stuff." I think that's the technical term for it anyway.

Gary

And I think that cycle goes like this:

Enthusiasm --> Spend Money --> Hard Work --> Good Stuff --> Bad Stuff --> [Start over at: Spend Money] :-D