Stopped Carbon Dosing.....Now What ?

[AmherstReef]

After carbon dosing (75/25-vodka/vinegar) for over three months, I slowly backed off then stopped because of a worsening cyano problem. At the time my nitrates were 0 and phosphates were reading .06 -.09

Its now been a week since I stopped carbon dosing and I have some good and bad results.

The GOOD
- My corals look great, great polyp extension on the SPS and my Hammer and Gonioporpa are plumped up and looking huge. May be related to the nitrates bumping up to .02

The BAD
- My Cyano problem has gotten even worse even though my phosphates are reading a deceiving .039
- The glass and back wall are once again covered in green dust algae.


So the question is what do I do now, corals look great but the tank looks like crap, I'm still running GFO which isn't helping, I have also started weekly water changes instead of my usual bi-weekly.

Seems like a catch 22..........Help !!!

 

[Randrew215]

I'm surprised the GFO isn't helping. I dose carbon and use cyano as an indicator to change my GFO, as it (cyano) quickly abates with replacement. I get cyano around week 3 and change GFO around week 4.

 

[tmz]

Here's my response from the identical Reef chemistry forum thread you authored:

http://www.reefcentral.com/forums/showthread.php?t=2305892

I saw it there first.

Chris, I would not use chemiclean. nor light depravation,particularly with the corals you have.
Personally, I'd siphon the cyano daily ,keep up the gfo and watch the PO4 and NO3 levels. If needed after a couple of weeks or so for things to settle down ,I'd consider restarting soluble organics at a lower dose once you have some nitrate( say 0.5 to 1ppm ) and detectable PO4.
In the meantime siphon the cyano, blow out and siphon detritus, skim heavy and use gac since I suspect you now have excess organics in the water fueling the cyano both from the earlier nitrogen deficiency we discussed in the other thread and the waning of the bacteria. I'd lighten up on feeding for a little while too.

 

[AmherstReef]

Thanks Tom, I'm definitely not using chemiclean or going lights out. I'll suffer through it until I can fix it right and see what happens after another week of siphoning etc, then go from there.

Thanks for the advice Tom.

On a side not, after all the talk about nitrates and carbon dosing in recent threads, it was very interesting to see how much better my corals looked after my nitrates went from 0 to .02

 

[der_wille_zur_macht]

What do you have on the tank for a skimmer?

 

[AmherstReef]

Been running an SWC 160 cone for the two years that the tank has been up

 

[tmz]

Nitrogen deficiencies.sometimes, do seem to play a role in tanks dosed with organic C . This is generally not the case in fed tanks and/or those with a good sized fish population where the supply of N is usually plentiful.
When zero N or something very close to it occurs , the bacteria that normally use N,the organic C and P are likely N limited leading to a buildup of unused C which gives an advantage to cyano over other competitors since most cyano strains can produce their own fixed nitrogen and the competitors can't. There may be other actions/ reactions in play but that scenario seems plausible to me .

I've been dosing vodka and vinegar for over 5 years with very good success. I like to keep nitrate in th 0.2 to 1.0 ppm range per the Salifert test( just a tinge of pink). If it drops to undetectable(clear) a very tiny amount of sodium nitrate or an ammino acid like aspartate can reset it,ime. A little extra food may help as well but food also brings in more organics and phosphate.

 

[Gary Majchrzak]

Chris- have you tried leaving N alone and just going after PO4 using LaCl3?

 

[AmherstReef]

Chris- have you tried leaving N alone and just going after PO4 using LaCl3?

Not yet, I think my choices may trying LaCl3 for phosphate reduction or try dosing carbon again but additionally dosing to keep nitrates up.

I have skimmed your thread but I'll have to give good read.

 

[tmz]

Another alternative to organic carbon dosing is more gfo,regenrated to save on costs for PO4 control. You don't seem to need the organic C for nitrate at least at the moment. Right now I think you need to get any excess organic C organics out while maintaining low PO4 by whatever export method you choose.

 

[AmherstReef]

That's definitely the plan for now, get this cyano under control before any other changes. I would be happy to just use GFO for control, but its exhausting so quickly is getting very expensive.

 

[tropills]

Have you ever tried dosing sugar. ? Quite a few years ago I did with VERY good results, its cheap and from what I experienced none of the side effects of the other carbon methods .. JMO

 

[Gary Majchrzak]

I experienced none of the side effects of the other carbon methods .. JMO

what other side effects?

 

[tropills]

Guess I should of clarified, when I stopped dosing sugar, I didn't experience any regrowth of cyno or brown algae, my system was not effected when I stopped dosing sugar unlike the starter of this post that was using another carbon source..

 

[Gary Majchrzak]

I'm trying to wrap my mind around all of this C dosing.

Why would vinegar/Vodka dosing have a different effect than sugar dosing? There must be reasons... but if zero nitrates were Chris's problem.... doesn't sugar dosing as well as Vodka/Vinegar dosing lower nitrates? (assuming dosing is all done properly).

Maybe Tom can explain................

 

[tropills]

Oh believe me Gary, it made my head hurt for years trying to figure it out.. I dosed sugar for phosphates not nitrates though, when I dosed my nitrates were barely detected, but my phosphate was extremely high, I'm sure the P was using the N as a food source but the P was what I was targeting ... maybe I put the cart before the horse but it worked out well in my circumstance..

 

[tmz]

Sugar is a monomer. It's trouble, ime. Leads to coral recession and browning. Many have trouble with it. I no longer use it. Excess glucose has been related to coral mortality in at least one study. Some who have dosed it do cite a more rapid reduction of the bat in nitrate than with vodka or vinegar ; perhaps. due to the fermentation process as sugar it turns to ehtanol ;but that is not the issue in the op's tank; his nitrate are zero.
Many have had trouble with sugar dosing including cyano bacteria and other bacterial blooms as well as coral recission and death. When I tried very small amounts on two occasions the negative effects results were obvious in my fleshy lps and my rbta(entmacea quadricolor) anemone

Here's the difference in an over simplified glance at the bacteria cascade in acetogenesis:

Start with carbohydrates( potatoes, rice ,grains bio pellets and so on), These are complex ploymers, linked together in chains by carbon. Bacterial straiins break them down taking the energy from the bonds leaving to monomers( sugars),less complex chains that are more miscible( they diffuse through the water more freely than ploymers).

Sugars (monomers) are then broken down to ehtanol (vokda) by other bacterial strains.

Ethanol(vodka) oxidizes in water to form acetic acid(vinegar/ask ethanoic acid).

Vinegar (acetic acid) goes to acetate in water which bacteria consume and is also useful to other living things.

So, all of it goes to acetate eventually but with vodka and/or vinegar you avoid the bacterial activity associates with the breakdown of polymers and monomers.

Biopellets were touted to localize the bacterial activity to the pellets ;thus , monomers hould not be a concern. Disapointingly, that's not the case as bacterial and their by products do enter the water column quite readily as evidenced by bacterial blooms etc; perhaps not as readily as free dosed sugar though.


This is one of the reasons I prefer ethanol and or acetic acid.

 

[tropills]

I understand the physics, in some cases wouldn't MEK do the same as vodka/vinegar. ?? Its a acid , alcohol base.. its a extremely high dose and understandably hard dose to compute but could bre accomplished .. correct. ?

 

[tmz]

I'm trying to wrap my mind around all of this C dosing

It's a bear.

It can,however, allow a mixed reef tank to thrive without very much if any nuisance algae at feeding levels impossible , otherwise,ime.

I tried dosing vinegar about 8 years ago ans stopped because I realized I wanted to know more about the risks and exactly what was happening before continuing. After a two year plus year hiatus, I started again armed with new thoughts that I understood it after conversations with Genetics, Randy Farley and mesocosm as well as a lot of reading. Been doing it for 5 years with really good results by any measure and still don't understand it the way I want to. I do get a glimpse of light now and then which keeps me poking away at it.No one understands the role of organics in the oceans much less reef tanks as far as I know. Probably wont at least for decades.

Consider the complexity. When carbon is introduced ,you up the ante in terms of the life energy in the tank , change the fundamental ratio of C:N and the overall biology of thr tank. All that sun enegry is trapped in the carbon bonds by photosynthesis primarily and it is scavenged aggressively by living organisms .

The biology of the tank is changed, bacteria and their by products are cultured that were there before but perhaps not dominant. Micro fauna reacts to changes in the food chain and changing DIN ,DOC an Pi levels.The activities of competing organisms like cyano, diatoms and other phyto plankton ,algae , corals and their symbionts as well as bacteria strains change with the changing resources . Hierarchies are upset and new ones are set up . This sometimes leads to an advantage to cyano as an example during the early stages .

Going slow is very important to minimize risks as the new biology evolves. It is not a plug and play method and carries some risk.

Consider that the organic mix is changed in ways you can't detect and there are 100s of thousands of organic compounds if not millions. Little is known about many of them.Also, each tank can be quite unique with numerous external variables in play.Bacteria take up N,P and C but also metabolize some metals and minor elements too.
You have probably seen this thread but for the benefit of other readers it might be of interest:

http://www.reefcentral.com/forums/showthread.php?t=2134105&highlight=organic+carbon+dosing

 

[tmz]

I don't know why you would try(MEK) butanone(CH8O) or how it would work. Not much carbon in it relative to ethanol.

. It's not very soluble and gives you 8 H ions for each C as opposed to ethanol which is very miscible in water and at C2H6O gives you just 3 H ions for every 2 carbon. Acetic acid (vinegar is C2H4O2) and is highly miscible btw.