Carbon dosage tuning question

[xTJxSLIMx]

I have a feeling I am going to be ordering a hanna phosphorus ulr about a week after getting the salifert...;Facepalm I hate color matching...

 

[cooltowncorals]

I don’t agree. Carbon dosing often leaves residual phosphate when used to control nitrate because it can consume more N than P due to denitrification.

I used the combo of organic dosing and GFO (and macroalgae) for years and think it a good combo.

I think I was trying to make the same point that if you are if you don’t have high enough nitrate levels prior to carbon dosing you won’t get your phosphate levels as low as you want by carbon dosing alone.

Both the zeovit system and Red Sea actively state not to use phosphate removers with their carbon source I don’t understand why but seems fair to pass along the warning. A side note Brightwell does encourage phosphate removers with their reef fuel. I have personally found zeovit and red seas product use information to be clear and accurate.

I did not have good luck carbon dosing with macro algae and preferred dosing nitrates to messing with cheato.

 

[Belgian Anthias]

I don’t agree. Carbon dosing often leaves residual phosphate when used to control nitrate because it can consume more N than P due to denitrification.
.

But it can also do the opposite as carbon dosing may create a high C:N ratio and denitrification may be replaced by DNRA .
As carbon dosing inhibits nitrification the denitrification capacity present in a nitrifying biofilm will be lost which will increase the availability of Ammonium-nitrogen considerably. As carbon dosing is still not dosed on a known parameter carbon dosing may often lead to overdosing creating a high C:N ratio. As fast growing bacteria use ammonium-nitrogen the C:N ratio is based on the available ammonium-nitrogen and not on nitrate-nitrogen availability.

 

[Randy Holmes-Farley]

As carbon dosing inhibits nitrification the denitrification capacity present in a nitrifying biofilm will be lost which will increase the availability of Ammonium-nitrogen considerably. As carbon dosing is still not dosed on a known parameter carbon dosing may often lead to overdosing creating a high C:N ratio. As fast growing bacteria use ammonium-nitrogen the C:N ratio is based on the available ammonium-nitrogen and not on nitrate-nitrogen availability.

I do not concur with that sentence. It doesn't make sense to me. There's a bit of circular reasoning, IMO.

How do you propose that carbon dosing "inhibits" nitrification? I agree it may reduce nitrification by consuming ammonia and thereby reduce ammonia available for nitrification (that is not inhibition). If ammonia is produced by DNRA to a degree that ammonia is actually higher than without it (not shown in a reef tank to be true), then nitrification is not inhibited by low ammonia or for any other reason (how would it be?).

 

[Belgian Anthias]

But it can also do the opposite as carbon dosing may create a high C:N ratio and denitrification may be replaced by DNRA .
As carbon dosing inhibits nitrification the denitrification capacity present in a nitrifying biofilm will be lost which will increase the availability of Ammonium-nitrogen considerably. As carbon dosing is still not dosed on a known parameter carbon dosing may often lead to overdosing creating a high C:N ratio. As fast growing bacteria use ammonium-nitrogen the C:N ratio is based on the available ammonium-nitrogen and not on nitrate-nitrogen availability.

Of coarse the C:N ratio is determined taking in account is the nitrogen source used. For denitrification and DNRA this is nitrate-nitrogen. For carbon dosing inducing fast growth the nitrogen source is ammonium-nitrogen ( TAN). r-strategists prefer ammonium-nitrogen . Forced to use nitrate-nitrogen the growth rate may be limited to become +- 8x slower and they will not any more be able to win the battle for available building materials.

 

[Belgian Anthias]

I do not concur with that sentence. It doesn't make sense to me. There's a bit of circular reasoning, IMO.

How do you propose that carbon dosing "inhibits" nitrification? I agree it may reduce nitrification by consuming ammonia and thereby reduce ammonia available for nitrification (that is not inhibition). If ammonia is produced by DNRA to a degree that ammonia is actually higher than without it (not shown in a reef tank to be true), then nitrification is not inhibited by low ammonia or for any other reason (how would it be?).

For me "inhibition" means also "suppression; hindrance; impediment; enz If you mean " inhibition" as used in " inhibition of enzyme function" one may say that the presence of ammonium " inhibits nitrate reduction " but one may not say carbon dosing "inhibits" nitrification. Are we "reducing" ammonium by heterotrophic assimilation? This is not the discussion that needs to be conducted.

Carbon dosing depletes ammonium-nitrogen availability and the r-strategists will outcompete the nitrifiers and denitrifiers also for other essential building materials. ( 40x more building materials are needed to reduce the same amount of ammonium-nitrogen) The nitrification capacity will be reduced , may even be removed. This means ammonia may remain if other building materials can not be provided in time for fast growth and they will not be available to reinstalling nitrification capacity. As ammonia inhibits nitrate-nitrogen assimilation this is an issue which may not be overlooked.


Why nitrate and phosphate may build up in a well-lit aquarium and is not used up by photo-autotrops? An important question to be answered before starting dosing carbon!

it can consume more N than P due to denitrification. May the denitrification capacity of a marine aquarium increase due to carbon dosing? Due to high oxygen consumption increasing the anoxic zones? Reducing nitrification capacity also reduces denitrification capacity in comparable quantities.
May be assumed certain processes as DNRA do not take place in a marine aquarium because it is not shown, because it is not investigated? DNRA was isolated on most places where it was expected to happen and was looked for and was found in bio-filters.
It was found DNRA may outcompete denitrification in OMZ zones with higher as normal C:N ratio.


Understanding what happens in the limited environment of a reef aquarium when dosing supplemental carbon.
A lot of well documented information is available about the effects of changing C:N ratios in a biological active and isolated environment.

 

[Randy Holmes-Farley]

I'm not following how what you suggest is a problem when organic carbon dosing.

Perhaps that is the issue. You suggest an imperfect understanding of what is happening in reef tanks, and I agree.

Then you suggest there's some lurking problem reefers will encounter when carbon dosing. Like rising ammonia??

That is the part I do not see happening, or any evidence for it happening.

 

[Belgian Anthias]

I'm not following how what you suggest is a problem when organic carbon dosing.

Perhaps that is the issue. You suggest an imperfect understanding of what is happening in reef tanks, and I agree.

Then you suggest there's some lurking problem reefers will encounter when carbon dosing. Like rising ammonia??

That is the part I do not see happening, or any evidence for it happening.

You suggest I have an imperfect understanding of what happens in a reef tank, not me. Because I disagree with the way you promote carbon dosing? I may have insufficient knowledge of chemics but I know what I am talking about. My picture of what happens in a reef tank is much closer to reality as just taking in account what may happen when a carbohydrate enters the water. This is of minor importance in relation to all the rest what may happen due to adding supplemental carbon. Carbon dosing may take over the ammonium reduction capacity and a temporary ammonia build up is a logic outcome when doses are not matched to the needs. Even for me. Is this good husbandry?
Fish die and a lot of fish die of ammonia poisoning as most fish carry an ammonia history. Not by carbon dosing! Why not?

When no or limited autotrophic ammonia reduction capacity is present ammonia may build up any time for a period of time when carbon is dosed the way it is done. Even I am able to follow the logic in this knowing bacteria prefer ammonia- nitrogen and nitrate-nitrogen assimilation is inhibited by the presence of ammonia.

I also do not see it happen but I do not have to see it to know it may and will happen. A lot of fish have died and will die in captivity of ammonia poisoning and carbon dosing the way it is done f may accelerate the poisoning process.
What may be the cause of dead of a fish kept in a carbon dosed system. The first thing I will think about is ammonia poisoning. Does this mean the fish died of ammonia poisoning caused by carbon dosing? Who will tell!
Most risk is created when carbon dosing is stopped or interrupted suddenly. This should be done gradually over a long period of time to be sure sufficiency carrying capacity is installed. Most users have no clue of the C:N ratio they are maintaining by dosing carbon and the carrying capacity may be removed completely when dosing is stopped suddenly.

Ignoring the fact that carbon dosing the way it is done may cause ammonia poisoning is closing the eyes for reality. Since 50 years new systems must be cycled for at least a month to install an appropriate carrying capacity before adding fish this to prevent ammonia poisoning. But removing this installed capacity in an established aquarium partially or completely is considered not a problem;

All this just to reduce harmless nitrate. Faut le faire.

 

[xTJxSLIMx]

Most risk is created when carbon dosing is stopped or interrupted suddenly. This should be done gradually over a long period of time to be sure sufficiency carrying capacity is installed. Most users have no clue of the C:N ratio they are maintaining by dosing carbon and the carrying capacity may be removed completely when dosing is stopped suddenly.

I read a few forums when setting up my tank that when ammonia reaches zero after last fish is added you no longer need to test for it or nitrite. What you mentioned makes sense, I did suddenly cut off the nopox in fear of the white slime. It just made no sense to me that the nopox was working perfectly, even too good when I reached zero nitrate. After slime started to clear up I continued to dose with poor results. Just checked my ammonia .25, nitrite 0 and nitrate 20. Now adding some Dr. Tims and fully opened up my skimmer gate valve for 48hrs...

So if I'm understanding this correctly I essentially killed off a percentage of my bacteria population in a 3 month old system while being fully stocked. Because I slightly overdosed nopox and stopped cold turkey. ;Facepalm

 

[Randy Holmes-Farley]

You suggest I have an imperfect understanding of what happens in a reef tank, not me.

I'm suggesting we all have an imperfect understanding.

For example, NONE of us know how much N is taken up by corals, algae, or bacteria, as ammonia, nitrite, or nitrate in our reefs.

 

[Randy Holmes-Farley]

So if I'm understanding this correctly I essentially killed off a percentage of my bacteria population in a 3 month old system while being fully stocked. Because I slightly overdosed nopox and stopped cold turkey. ;Facepalm

That's a possibility, for sure, but not the only explanation. It is a potential reason to wean off of carbon dosing just as one might wean off of macroalgae or an ATS whose sudden removal might allow ammonia to rise.

 

[xTJxSLIMx]

I recieved my salifert phosphate test kit. It read ~1.5ppm when api read .25-1ppm. Ran gfo since thursday and now salifert is reading .25 po4. I will continue to run gfo and add Dr. Tim's one and only until I start seeing ammonia drop and phos get down to at least .03.

Any advice on ramp up and down time frames of nopox? Like 1ppm a week?

 

[Randy Holmes-Farley]

I’m not sure there’s a good reason for slow ramp up, although many people do.

Lots of people ramp down dosing when nutrients hit their target. I’d suggest a week ramp down if you are going off it entirely.

 

[xTJxSLIMx]

I’m not sure there’s a good reason for slow ramp up, although many people do.

Lots of people ramp down dosing when nutrients hit their target. I’d suggest a week ramp down if you are going off it entirely.

Yes your right. I notice on the red sea instructions it does give me the impression that above 10ppm nitrate 3ml per Xgallons. Never says ramp up to or slowly increase to X amount. But for sure gonna ramp down over a weeks time to a maintenance load once I get closer to 1-3ppm N03. Thanks

 

[Randy Holmes-Farley]

Yes your right. I notice on the red sea instructions it does give me the impression that above 10ppm nitrate 3ml per Xgallons. Never says ramp up to or slowly increase to X amount. But for sure gonna ramp down over a weeks time to a maintenance load once I get closer to 1-3ppm N03. Thanks

Some articles, like this one, suggest very slow ramp up. I don't buy the importance of that:

Vodka Dosing...Distilled!
http://reefkeeping.com/issues/2008-08/nftt/

 

[xTJxSLIMx]

I want to add that I just did a 25% water change, ammonia did go near zero, nitrate stayed at 40. (API kit, waiting on salifert in the mail) I tested twice and checked api on another tank and it is as accurate as api can get. So why has my nitrate not budged? Kept my nopox at 4ml daily, white slime in skimmer, return line, overflow box, in cheato... This is getting annoying. Any recommendations?

 

[Belgian Anthias]

Yes your right. I notice on the red sea instructions it does give me the impression that above 10ppm nitrate 3ml per Xgallons. Never says ramp up to or slowly increase to X amount. But for sure gonna ramp down over a weeks time to a maintenance load once I get closer to 1-3ppm N03. Thanks

At 1 ppm nitrate or 20 ppm nitrate the same amount op nitrogen must be assimilated to be able to lower the level, a bit more as the daily nitrogen overproduction daily , enough to support the daily growth rate replacing the previous autotrophic ammonium -reduction capacity.
As carbon dosing induces bacterial growth primordially using ammonia-nitrogen and not nitrate -nitrogen , when the nitrate level is 0 still the daily nitrogen overproduction must be incorporated in growth ( maintenance dose?), not only to control the nitrogen level but to sustain the carrying capacity of the system as the nitrification capacity will not be able to do it as it is removed partially, maybe completely. As most users have no clue of the daily nitrogen overproduction and do not know they have been overdosing or not ( removed the autotrophic carrying capacity partially or completely), ramping down carbo-hydrate doses should be done gradually over a period of at least a week, better two weeks, to be sure sufficient autotrophic ammonia-reduction capacity to support the present bio-load is reinstalled.

 

[Bill Urbanski]

Ok. Need to seek some guidance. My tank is almost 3 years old and I have been vinegar dosing for about a year. I had it set to dose 100ml a day in a 150 gallon system. I started to notice a film on the rocks so I cut back on the dose to 75ml a day. I recently took my water to my LFS to test and they got a slight ammonia reading. Would that be from the reducing of the dose of vinegar? Should I have left it at 100ml even seeing a slight film on my rock?

 

[Bill Urbanski]

That's a possibility, for sure, but not the only explanation. It is a potential reason to wean off of carbon dosing just as one might wean off of macroalgae or an ATS whose sudden removal might allow ammonia to rise.

Randy is a change from 100ml a day to 75ml enough to cause ammonia? I’m dosing vinegar in a 150 gallon system and recently had the LFS test for me and they got a slight ammonia reading. Has me concerned.

 

[xTJxSLIMx]

Got my salifert nitrate test in today. Its reading 10ppm. I had left my doser at 1ml daily nopox. I also noticed white mucus dissipate. I had also lowered my feeding quite a bit. I was feeding about 1.5 blister pack daily. I now cut the blister pack into 1/4's and feed 1/4 cube mysis in the morning, 1/4 mysis and a 1/4 homemade shrimp, scallop, fish meat cube at night. (3/4 blister pack total daily for my 40g w/ 7 fish)