Baffling nitrate results???

[jeffpettis]

So to start this is my first post on the forums all though I have been following this site for years.

A little background. I have a 60 gallon reef with a 20 gallon sump. The display tank has around 60 pounds of live rock 8 large (7"-8") hairy mushrooms, 1 toadstool, numerous small red and blue mushrooms, a couple of rock anemones and some Kenya trees. The sump has about 8 to 10 pounds of live rock as well.

This tank has been set up for around 2 years and doing great. All the fish and corals seem to be thriving.

The problem is I always have high Nitrates. Always! I don't think I have ever had a Nitrate test below 50ppm. I tested this morning and every other parameter is spot on.

Temp 78
Salinity 1.023
PH 8.2
Phosphate 0.03
Ammonia 0
Nitrite 0
Nitrate 100+

Mind you this is not a spike. This seems to always be the norm. I have done everything I know to do to try to lower the Nitrates and nothing, NOTHING, ever seems to do it.

As a side note all of my water, top off water and water change water is RO water. We even have our well water that feeds the RO system tested every 6 months for Nitrite and Nitrates and even straight tap water here on the last test was 0.02ppm.

Needless to say I am at a loss and really need some advice.

Thanks in advance...

[tmz]

Type of filtration in use?
GAC in use?
Skimming?
Detritus buildup?
Substrate if any; how old ?
Fish population?

What specifically have you done to reduce nitrates ?

BTW, the corals you listed should be ok with high nitrates. Even so, 50 to 100ppm would be out of my comfort zone .

[jeffpettis]

The output from the tank runs into the sump through a filter sock, then through a chamber filled with live rock and a deep sand bed then over to the protein skimmer chamber where I have a Coralife 165 skimmer then finally to the return pump area.

I do have a mesh bag filled with GAC in the return chamber. ( I know, not the most efficient way to do it)

I don't notice much if any detritus.

The substrate is live sand (forgot the name), that gets stirred up and vaccumed pretty often.

And the fish population... Didn't realize I forgot that in my original post. 1 Yellow Tang, 2 clowns, 2 cardinals, 2 chromis, 1 red fire fish, 1 watchman goby, a cleaner shrimp, a few peppermint shrimp, 2 small emerald crabs, and numerous snails and hermit crabs for a cleanup crew.

And your last question. Mostly water changes, and more water changes, and a few more water changes...LOL! Also tried some de-nitrate a couple of times with, I feel, no results whatsoever, I have also reduced feedings a few times for a while to see if that was contributing to it.

But here's another question to go along with the original problem. Shouldn't I be having some kind of algae outbreak with nitrates that high? In two years I have not had any algae outbreaks except maybe a few spots of red slime or a few spots of hair algae hear and there.

[tmz]

Low phosphate could be limiting nuisance algae or herbivores may be controlling it well enough.

I had persistently high nitrates(50 to 80ppm ) in my system about 6 or so years ago. A remote deep sand bed , heavier gac use, macro algae refugium,extra live rock, increased water changes did little to help. Improved skimming helped some .More detritus siphoning helped some but not enough. Removed a 7 year old sand bed and that helped . Still wasn't doing much under 50ppm. Organic carbon dosing ,vodka/vinegar, did not move them after a couple of weeks of trying it. Ultimately a diy sulfur dentirator took them to near zero within two weeks. Then organic carbon dosing kept them there without the denitrator. For the last 5.5 years , I've relied on dosing vodka and vinegar in moderate amounts to keep nitrate and inorganic phosphate low . Despite heavy feeding ,PO4 is .02 to .04 ppm per hanah 713 with NO3 at <0.2ppm per the Salifert test kit.

[jeffpettis]

Thanks for the replies Tom.

I know I said in the first post I had "tried everything", let me rephrase that, everything I have tried so far has not worked. Big difference. :)

I am planning to do a very good cleaning, again, and do a couple of larger water changes over the next week or so. But something you said earlier got me thinking. I only clean and change my filter sock when it starts to get clogged, about once every other week or so, and it is normally pretty nasty when I change it. Could this be a "large" contributor the problem? I realize that if so this wouldn't solve the problem but I am trying to eliminate any sources of detritus build up to see what the actual culprit is.

[tmz]

The decaying matterin the sock will contribute some dissolved nitrogen probably as ammoinia which ultimately goes to nitrate . The culprit is an imbalance between the amount of input via foods and decay vs the output. More sources of dissolved nitrogen are entering the aqaruium than are being used or exported .

[jeffpettis]

So what would be the next step to use or export the dissolved nitrogen out?

Sorry if that sounds like a stupid question by the way...

[tmz]

Less food ,stonger skimming , a dentirator or organic carbon dsooing are a few options.

[jeffpettis]

I guess I will go ahead with the water changes I was planning to do this coming week. Would 3 or so large water changes, say 35-45%, in one week negatively effect anything?

Also I am going to start switching and cleaning the filter sock daily for a while.

And what de-nitrator do you suggest? Maybe something that I could put in a mesh bag in the sump somewhere? Or is this not effective at all?

As far as the food goes I only feed about three times a week as is (unless my wife is doing it without me knowing :inlove:) It's actually HER tank, I just get to take care of all the FUN stuff, if you know what I mean...:)

Thanks again.

[Richocet83]

This helped me cut my nitrates in half, especially if you're waiting for the sock to overflow before changing like I used to.

I guess I will go ahead with the water changes I was planning to do this coming week. Would 3 or so large water changes, say 35-45%, in one week negatively effect anything?

Also I am going to start switching and cleaning the filter sock daily for a while.

And what de-nitrator do you suggest? Maybe something that I could put in a mesh bag in the sump somewhere? Or is this not effective at all?

As far as the food goes I only feed about three times a week as is (unless my wife is doing it without me knowing :inlove:) It's actually HER tank, I just get to take care of all the FUN stuff, if you know what I mean...:)

Thanks again.

[jeffpettis]

I guess it just never occurred to me that that seemingly small amount of buildup would make a noticeable difference. We'll see what happens.

Also has anyone heard of this method of doing water changes where you, "Make up 20 gallons of fresh saltwater in front of your tank. Drain 10 gallons of tank water into the 20 gallons of new water, and let that mix. Pump 10 gallons of that water back into your tank, and let the power heads mix that water up in your tank for a minute or so. Then repeat this three more times. Dispose of the now polluted 20 gallons of water. Make up another 20 gallons of fresh saltwater, and repeat this procedure. As long as your temperature and salinity match the tank, your inhabitants won’t be affected adversely, and with each rotation of water, the nitrates are being diluted and removed from your tank."

Am I missing something or wouldn't a couple of large 25 or 30 gallon water changes in a week accomplish the same thing?

[waxhawreefer]

I have the opposite problem , zero nitrates but always .04 phosphates, and when Im lucky to get a reading of 0.0 phos I still have some kind of algae problem going on, but I read that there is a relationship between nit,phos, that they are both needed in some percentage to help coral growth, so if ur nit is high and you dont have an algae problem dont worry, maybe start some bio pellets

[ghostman]

I had a nitrate issue, and found a denitrator to be the ideal solution. They are simple, low maintenance, and do the job. I highly recommend using one like the Geo system. After the nitrates are done, it can be converted into a calcium reactor with a few extra parts.

[tmz]

I never heard of the method for salt water changes noted in your post. Don't see any benefit to it.;seems wastefull.
Large water changes may change levels and proportions of various elements in the aquarium water i. I'd personally limit water changes to 13% or 20% at a time with newly mixed salt water matched to tank water salinity and do several over the course of a week to achieve a reduction in NO3. Still ,you need to figure out where it's coming from and/or a method to export it continuously.

[jeffpettis]

I had never heard of the method I mentioned either but came across it while doing some research. It doesn't make much sense to me and seems counterproductive but I wasn't sure if I was missing something...

I am planning to do a few 20 gallon water changes this coming week to see if I can get them down to a more acceptable level.

[Randy Holmes-Farley]

IMO, the procedure mentioned above for water changes is needlessly long and tedious and not as efficient as simply drain and refill.

FWIW, I change 1% daily, automatically. :)