Jump to content
Innovative Marine Aquariums

Where did my nitrates go?


Wattman

Recommended Posts

While many complain about nitrates being too high, I am concerned that mine might be too low.

 

I have a fluval spec V set up for about 5 months now. I've always battled what I considered high nitrates since starting the tank, in the 10-20ppm range before 10-20% weekly water changes. After water changes it would drop in the 5-10ppm range. pH 8.2

 

Two weeks ago I woke up to almost zero flow and thought my mini-jet 606 was dying. I discovered that the stock nozzle had become clogged with quite a bit of mysis shrimp. After cleaning it was good as new. I'm thinking this contributed to my elevated nitrates.

 

This week I start mixing my saltwater to get ready for a water change, but before I start cleaning I decide to test for nitrates. To my surprise my nitrates BARELY register on my API test kit. I do a second test with the same kit to make sure I hadn't messed up and same result.

 

At this point I think the test kit might be going bad. I remember I had some back-up test strips made by Tetra (wally world cheapos). I don't normally use them, but they work in a pinch. Same result with the test strips where before they would clearly register nitrates now they read as close as I can tell to 0.

 

I have a small maroon clown in the tank since 5/28/14 (will move to 28 cube when larger) and numerous corals. I recently added a peppermint shrimp on 7/9/14. Is it possible the shrimp is cleaning up detrius that had previously been contributing to high nitrates?

 

It's my understanding that nothing consumes nitrates except denitrifying bacteria. I started out with all dry base rock and maybe it's finally starting to be productive in aiding in nitrate removal?

 

I'm worried that low nitrates will hurt my corals, I've read a little nitrate is good for their health. At this point do I just keep doing water changes even though the water is testing clean?

 

I have a red sea kit for CA KH and MG but I honestly haven't used it since corals have been doing great. I'm guessing water changes will only aid in replacing trace elements at this point.

 

Sorry for such a long winded post, but I'm just wondering if this is normal and if anyone else has experienced anything similar.

 

 

Link to comment

1) It's my understanding that nothing consumes nitrates except denitrifying bacteria. I started out with all dry base rock and maybe it's finally starting to be productive in aiding in nitrate removal?

 

 

Yes, bacteria will help to remove nitrate when tank's getting mature.

 

 

 

2) I'm worried that low nitrates will hurt my corals, I've read a little nitrate is good for their health. At this point do I just keep doing water changes even though the water is testing clean?

 

 

0 nitrate is best idea for all live stock and corals.

Link to comment

out of solution?



Im not sure I would trust a consumer colorimetric test to be all that accurate anyway. what's the resolution on it? +/- xppm?

Link to comment

Reading 0 Nitrates on an API test kit isn't meaningful at all. If you have a Salifert or Red Sea kit that is reading 0, then you can start to worry about increasing your nitrates. You are likely around 2-5ppm in realif your API is testing 0, which is a good level. If your nitrates were truly at zero, you would be in trouble.

 

2) I'm worried that low nitrates will hurt my corals, I've read a little nitrate is good for their health. At this point do I just keep doing water changes even

though the water is testing clean?


0 nitrate is best idea for all live stock and corals.


It really isn't - without nitrogen nothing can live. Also, having a nitrogen limited tank, as opposed to carbon or phosphorus limited, is about the worst you can have.

 

Sure, having an API nitrate test kit at 0 is awesome, but truly having no nitrates is terrible. I battled with truly low nitrates and hadn't seen any color on my Salifert nitrate test (meaning under 0.2ppm) which caused growth to slow way, way down and my acros color lightened significantly and even deeper colored acros were paled out. I actually dose my tank with Sodium Nitrate and add in AAs to keep my nitrates in the detectible range and my acros look much, much better for it and everything is growing much more rapidly.

 

An added side effect of having 1-2ppm nitrates and feeding heavily (along with my calcium acetate mixture adding carbon) allowed the tank to shift from being nitrogen limited to phosphorus limited, meaning I can run nearly no GFO and keep the flow through the reactor to a slow trickle and keep my phosphorus under 10ppb.

 

For a tank with 0.03ppm of phosphates, you want at least 0.48ppm of nitrates.

Link to comment

Which test would you recommend for greater accuracy?

Sorry I couldn't help you here as I am unfamiliar with the hobbyist level kits. Perhaps if you used a la motte or salifert, it would give you better resolution. I would play it by eye if I were in your position. While I understand it is a bit late if you SPS start to look pale, it's better than the alternative of loading your tank with nitrates.

Link to comment

As mentioned previously, I'd be willing to bet that your nitrates haven't changed all that much. I'd test with something more reputable, Red sea makes a good nitrate kit, along with Salifert and Elos. Before doing anything else I would seriously consider testing with another test kit brand. I've used an API kit once tested the same exact water at the same exact time and both API results were pretty drastic.

Link to comment

Your corals need nitrates and will use up the nitrates if they are fed enough plankton or get enough phosphates. The first link refferences a study showing nitrate uptake is limitied by available phosphate, either free or in food "(organic phosphate source)". (I have personally seen nitrates go from off the scale to 0.0 in about a little over a weeks time by doing a 12% water change with water from an established reef system that had phosphates.)

 

http://www.mendeley.com/research/high-phosphate-uptake-requirements-scleractinian-coral-stylophora-pistillata/

http://jeb.biologists.org/content/214/16/2749.full

http://wap.aslo.org/lo/toc/vol_48/issue_6/2266.pdf

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0025024

 

With regards to test kits, API test favorably against the other hobbyest kits. (Certainly verify any questionable test with another kit irregardless of the manufacturer.)

 

http://www.advancedaquarist.com/2012/6/chemistry

http://dfwmas.org/files/TestKitAnalysis.pdf

 

And don't be afraid of phosphates. Phosphates in both of these systems tested at over .4 mg/l with Elos Professional kit:

 


http://www.youtube.com/watch?v=-eCQSVdqBQA
Link to comment

Archived

This topic is now archived and is closed to further replies.

  • Recommended Discussions

×
×
  • Create New...