Nitrate Reduction 101 with sugar!!!

[kzooreefer]

from what i've read in the previous posts if every thing is going right you should see a reduction within the first few days. what type of test kit are you using? i really don't trust the dip stick type of nitrate tests as they are too error prone. i have the unique position of having my own water quality lab at work that i can use for testing my water.

 

[thriceanangel]

If they don't drop within a couple days, then I'd up the dose minutely. Like by a 1/4 -1/2 tsp depending on how much you're dosing. I wouldn't go more than a 25% increase per dose. What I did was to initially overdose ( wrong way to go ) so I don't know how fast they decline from a high amount. But after my initial overdoes, I still had like10-20ppm and just by upping the amount 25% they disappeared.

 

[kzooreefer]

i started one dose last night, i used 50 ml of a 10% sugar solution to the 15 galons of water in my aquarium. i made the sugar solution by mixing 1 tablespoon of sugar to 1/2 cup of di water. this dose is about 4 times what i would have gotten if i had added just 1/8 a teaspoon to my tank. it took a while for my skimmer to start seeing the sugar but eventually i did get some skimmate out, nothing out of the ordinary just the same old stuff i usually get. i took a nitrate reading after about an hour and then again this moring after 12 hours and the nitrates really haven't dropped considerably. i would expect this if the mechanism was bacterially driven as it will take time for the colonies specific to aerobic dentirifcation to mutliply and grow enough to significantly reduce the nitrate concentration. i do my usual water changes on saturday and am not sure i will continue with the sugar as i don't really have high nitrates, mine usually hover around 5 ppm. low nitrates could be a limiting factor in all this as it could be too low to really get a good bacterial colony to grow. in my opinion the bacteria involved in this process are not one of the normal, dominat inhabitants of the reef tank and would have to have a high enough concentration of a food source to really kick off their growth.

 

[guntercb]

Kzooreefer,

I like the test you did in the lab without the skimmer. So it seems that one needs a skimmer for the NO3 reduction to occur.

I need to read the article you attached. I know you don't think that the anaerobic bateria that reduce NO3 to Nitrogen gas need carbon, but I know the equations I see have C carbon in them to reduce nitrates to nitrogon gas. Is it possible that the anaerobic areas of the tank (sand bed and inside the live rock) use the sugar (carbon source) to convert the NO3 to Nitrogen gas. But if the bateria in the anerobic do not need or use Carbon then my theory is not good.

I will read your attached link when I get a break.

Thanks for doing the chemistry experiments.

Cheers,
Chris

 

[hansonfam]

Has anyone tried this with anemones or clams in there tanks? Because if it is anything compatable to the AZ-NO3 product than that product is not recommendd with these types of inverts. There are a couple reviews saying that product worked great but there clames and nems died? Is this the same type of idea that we have with the sugar or is it somewhat different?

Lisa

 

[kzooreefer]

i think everyone here will agree that there is always a risk of shocking your system if you drop contaminant levels too quickly. but so far in my experience i've only had a 10% decrease in nitrates in a 12 hour period, i get basically the same from a 10% water change. i have to run the test longer to see if i can get better results.

a lot of people in teh reef community believe that sugar is harmful to reefs and there is some research out there that others have linked to that seems to back up their claims but i haven't read it so i can't comment on that. what a lot of people on these sites do is google search a topic then find an article with a title that backs up their claim and they post it without reading it as evidence to back them up. once you actually read some of these articles they are way off thinking they back them up. i want to see facts not fiction that something does or does not work in an aquarium. if you post a link to an article at least read it first and make reference to it in your arguments pro or con. (guntercb, please don't take offense i'm not talking about you but about another site i was on. a responder put in a reply that dosing sugar is bad and here are three articles to back me up with no reference to what the articles are about or what they say in them).

As far as AZ-NO3 i believe i read in their marketing material that they have reformulated their product a number of times to address past problems. so maybe die off was one of their past problems.

 

[guntercb]

Kzooreefer,

I was gettting worried there for a minute. (-: I did do a google search and posted the articles that I found. I will admit I did not read the entire articles, but was looking for a chemical equation dealing with denitification to support that some equations say carbon is needed. (-: But yes Google can get us all in trouble. To easy to find something without knowing the complete picture. I know I am guilty occasional. (-: It is lunch. I am going to print out your link and read it now.

Lisa, I would be careful dosing anything. Be it calcium cholirde or sugar. I do dose items, but always be aware that when you add something to your tank you can possibly disrubt the balance.

Cheers,
Chris

 

[guntercb]

Kzooreefer,

I read the abstract of the article you linked. It states that a ratio of C/N of between 8 to 11 is optimal for biotreatment of nitrate using K. oxtoca. Now we just need to figure out how to get the correct ratio. So carbon is needed for K. oxtoca to convert nitrate. (at least that is what the abstract implies). So by dosing sugar or any carbon source could help if we have less carbon than this ratio or would hurt if we already have a higher ratio of 11 for C/N. I am thinking that determining this ratio is beyond us normal reefist?

Chris

 

[RichConley]

<a href=showthread.php?s=&postid=9242204#post9242204 target=_blank>Originally posted</a> by kzooreefer
the typically referenced species of bacteria that perform denitrification use nitrogen as their food (energy) source irregardless of the presence of carbon or not. energy is produced through a biochemical reaction the results of which ammonia is oxidized to nitrite and then to nitrate and eventually nitrogen gas as a final product. different bacteria handle the different stages of denitrification. the nitrogen is only used as a source of electrons (energy) to perform the biochemical reaction producing the true "food" and is not consumed. generally speaking these bacteria evolved because of a lack of another source of energy, carbon, sulfur or other. but i will freely admit that there are more explanations for the sugar effect than what i gave, there could be hundrerds of reasons why it works, and carbon enhancment could be one of them. if I had the full article it would be nice as there is no body of evidence and no results of testing and or conclusions.

Kzooreefer, you're missing the point. Its not Nitrosomas we're feeding with carbon here. Its different types of bacteria and plankton. THe nitrogen cycle has absolutely nothing to do with this.

 

[RichConley]

<a href=showthread.php?s=&postid=9256774#post9256774 target=_blank>Originally posted</a> by hansonfam
Has anyone tried this with anemones or clams in there tanks? Because if it is anything compatable to the AZ-NO3 product than that product is not recommendd with these types of inverts. There are a couple reviews saying that product worked great but there clames and nems died? Is this the same type of idea that we have with the sugar or is it somewhat different?

Lisa

I;'ve been dosing about 6 months. My 18" Sebae continues to grow like a weed, and my 8" derasa looks fine, and is growing.


"here are a couple reviews saying that product worked great but there clames and nems died? "

There are? I've never seen any. I've seen people kill whole tanks, but not anemones/clams specificanly. The method puts all sorts of extra bacteria in the water column. Clams are filterfeeders. They should love it.

 

[RichConley]

<a href=showthread.php?s=&postid=9258075#post9258075 target=_blank>Originally posted</a> by guntercb
Kzooreefer,

I read the abstract of the article you linked. It states that a ratio of C/N of between 8 to 11 is optimal for biotreatment of nitrate using K. oxtoca. Now we just need to figure out how to get the correct ratio. So carbon is needed for K. oxtoca to convert nitrate. (at least that is what the abstract implies). So by dosing sugar or any carbon source could help if we have less carbon than this ratio or would hurt if we already have a higher ratio of 11 for C/N. I am thinking that determining this ratio is beyond us normal reefist?

Chris

Gunter, it stands to reason that if you have measurable nitrates, you're below that ratio.

 

[kzooreefer]

guntercb:

i believe they are talking only about the C/N ration of sugar to nitrogen not total organic carbon in the tank. it could be roughly estimated by using the ratio itself. C/N = 11. If nitrates = 20 ppm the equation is then C/20 ppm = 11, hence C= 220 ppm. if you convert this to a molar concentration then you should be able to figure out the amount of sugar to add through a molar mass calculation and % mass. i'm not good at basic chemistry anymore and need a textbook which i have at home to figure out how to do it. seems like it might be an awful lot of sugar to me though so maybe i'm calculating this wrong through the ratio. i'll bring my textbooks in and see if i can figure it out.

 

[RichConley]

kzooreefer, thats not the way it should be dealt with. If hes got measurable nitrates, then hes most likely carbon limited.

Now, we're talking 11:1 carbon to nitrate, but depending on the complexity of the sugar we use (theres way more than one atom of carbon in a complex carbohydrate) its probably much lower.


IE, there are 12 carbon atoms in a single sucrose molecule, so it may actually be close to 1:1 if using sucrose.

 

[hansonfam]

Oh and i am not saying that it happens with everyone but here is the reviews that i read about the procuct.:
http://www.marinedepot.com/md_optRe...=CP2151&description=AZ-NO3+Nitrate+Eliminator

Most said it was fine but there were a couple that stated with nems and clams it did some damage. And i guess you are all right that there is a risk with anything that you dose in our tanks. I think i will just start out with a/8 of a teaspoon of sugar add the airstone to the sump and cross my fingers it doesn't kill anything off

Lisa

 

[RichConley]

lisa, my issue with AzNo3 is that yes, its sugar based, but we have no idea what the heck else is in it.

It may be sugar with an added floculant to make the bacteria easier to skim, and that floc is causing clumps of dead bacteria to clog up clams... who knows?

It could be reall low oxygen levels bothering things. Theres no way to tell.

 

[kzooreefer]

i did a really basic calculation based on the molar precentage of carbon in sucrose, which is 42%. I come up with an equation:

0.10 grams sugar X gallons water in tank X ppm NO3 as Nitrogen

(4.2 grams of sugar = 1 teaspoon)

So for a 10 gallon tank at 10 ppm nitrate as nitrogen you would need 10 grams of sugar or about 2 1/2 teaspoons of sugar. this is a lot more than what was originally posted, i believe 1/8 or 1/4 a teaspoon to a 25 gallon tank but is still less than what i dosed my tank with last night. of course my math could be way off as i just did a quick and dirty estimation.

 

[thriceanangel]

I dosed 1 table spoon to my 100 gallon system, and I nearly couldn't see to the back of the tank... I was pretty worried. I don't think I'd dose that much.

 

[kzooreefer]

i put probably the equivalent amount in my 20 last night and it didn't turn cloudy. i don't see anything in sugar that could cause that to occur. of course now that i think of it i didn't turn my carbon filtration off so i'm sure that picked up some of the sugar but my skimmer did foam for about 3 hours last night after i put the sugar in so it didn't get it all but i do think the majority of it came out in the skimmate.

 

[kzooreefer]

i also think that the original posts idea was to slowly build up the sugar levels, start out low and then add more, over time, wait a couple of days between small doses, i'm sure the C/N ratio would then eventually reach 11 facilitating the bacterial growth.

 

[guntercb]

RichConley,

I don't know if I agree if you have measurable nitrates you are below the ratio. The ratio is the ratio that allows the K. Oxtoca to grow the fastest. You may just not have enough bateria to conert the NO3 but you could still have the correct ratio of C/N to yeld 11.

Example, you could dose lots of sugar and make the ratio above 11 and you would still have NO3.

Kzooreefer, If it is the amount of C from sugar you are right it would be easy to calulate. But I would think that the amount of organic carbon in the water would have counted. I know that wastewater plants only dose a carbon source if they influent is not already high enough in carbon for denitrication.

Thanks,
Chris