Nitrates 1.0

[Anonymous]

My reef tank has been running continuously for approx 3-4 years. It's mostly soft corals and a handful of fish. Typically most parameters are within the usual recommendation except in the summer when the temp goes up. The one thing that somewhat concerns me is my Nitrate level is typically at 1.0. I don't recall it ever going much below that.

I have always had approx. 1 to 1 1/2 inches of live sand that I thought should help. I also have a sand stirring starfish that does a great job of moving it around, even to the 1 inch level.

I do periodic water changes of around 5-10% every other month. I dose with Kalkwasser and have what I consider to be a decent protein skimmer. My question is whether I should be concerned about this level of Nitrates?

 

[Anonymous]

If corals and fish are happy and no unwanted algae then I wouldn't change a thing......

Also the test kit may have a slight variance and may not really be 1.0 ppm.......



[This message has been edited by David Grigor (edited 20 January 2000).]

 

[Anonymous]

nitrate build up is normal as a tank ages. water changes are great and lower pollutants but it takes to many to get nitrates down. the only way i can think of is a deep sand bed or plenum or denitrifying filter that uses a carbon source. like David posted before me, if corals aren't complaining i wouldn't worry. you can bring it down slowly be doing more frequent water changes. good luck

 

[Anonymous]

Would additional sand help? I've always been concerned that too much sand would tend to get dead spots and then really cause problems.

Are there some corals that are more susceptible to Nitrates than others?

George

 

[Anonymous]

George:

What units are you reporting nitrate in? If it is ppm nitrate, or even ppm nitrate nitrogen, there is absolutely nothing wrong with 1 ppm nitrate.

Many tanks (mine included) run at higher levels, even with sand beds. I have no algae problem, and am happy with the success of my tank (now 5 years old).

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Randy Holmes-Farley

 

[Anonymous]

Hmmmm, that's interesting. I guess I could add even more sand and see what happens. Other than the hassle of adding sand I don't see much of a down side.

There was a point where I was not regularly using KW so I think you may have good point about the dissolution.

I did catch that you said "most people". I take it that there are others that don't think that way? It's been so long ago that I don't recall why I settled on that amount but it probably had to do with what I was reading on some forums and what I saw in the tanks I wanted to mimick.

I even recall a video I have from Julian Sprung that mentioned a bare bottom tank for beginners. I was going to do that but the consensus at the time was to use sand for denitrificaiton. I think the recommendation for the bare bottom was for the ease of keeping the tank free of accumulated detritus.

George

 

[Anonymous]

Loss of gravel may be due to the abrasion of particles as well. As animals move through the sand (especially if they eat it) the sand will get smaller and smaller. This will compact (for lack of a much better term) and create a shallower sand bed.

I don't think that more sand would hurt. This would allow a necessary dead space to convert nitrate to nitrogen gas. Add a little at a time and it should help. Surely wouldn't hurt. I agree that if you don't have any noticable problems in the tank then the nitrate isn't an problem. If you want to get rid of it though add sand, change water more often and take care to not overfeed.

 

[Anonymous]

George:

<<I did catch that you said "most people". I take it that there are others that don't think that way?>>

Well, I was allowing for other opinions that might be perfectly correct. I've never seen a definitive study of how much is needed. Two inches is certainly enough for denitrification as I know people with such tanks who have undetectable nitrates. I've not seen similar results with significantly less than that, but I'm not saying it can't be true.

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Randy Holmes-Farley

 

[Anonymous]

I believe it is 1ppm "nitrate". It's been that way for as long as I can remember. Occasionally it may dip a little below that but for the most part it stays right at that level.

One interesting thing to note about my sand bed is that over time it seemed to have shrunken. What I mean is that I had 1 inch across the entire bottom. After a year or two the level diminished to about 1/2 inch.

Now I know some of it got pushed up against the base rock. I imagine some of the more organic materials probably got used up somehow. Also the larger particles eventually worked their way to the surface of the sand but I didn't expect to have to replenish that much. I added more sand to put me back to the 1 to 1 1/2 inch level but it really never changed my Nitrate levels.

The down side of the additional sand was being the recipient of some more bristle worms. I had a bunch of them in my initial rock. I don't recall who said it here, but I agree....I am always a bit hesitant to stir sand or grab rocks without looking for these things....OUCH!

George

 

[Anonymous]

Given the relative thinness of your sand, I'm frankly surprised that the nitrates are as low as they are. Most peope seem to think that denitrification requires a couple of inches or more.

The disappearance is presumably due to dissolution. If you aren't keeping the tank above saturation with respect to calcium and alkalinity, this will be especially fast. If you are, then dissolution will only take place lower in the sand bed where the pH is lower. Thus, dissolution may take place, but will be much slower.

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Randy Holmes-Farley