Is Carbon, Nitrate, and Phosphate Dosing Bad For the Hobby?

[jda]

I found one of them... in the SPS Forum Thread Here (post 128 in case this link does not work right). See, I told you all that my memory sucked since I cannot even get the forum right. In any case, read to post 141. There was another, but no quick luck searching gmail.

He links a very long peer-reviewed study that is a boring, but awesome read.

Regarding the 30%, it does not matter if a skimmer can get nearly all of the proteins before they become DOC.

I will search for another few minutes to find his comments when this study came up again... they blend very well with these and he offered some opinions more directly to take the Feldman study at arms-length whereas he just kinda implied it here.

This is the best line, for me (in post 141)... to each their own... Since Feldman relies almost exclusively on skim mate and another really smart guy says that you cannot...

While he and I may not be in perfect agreement on the underlying physical chemistry principles involved in every aspect of his experiments, the primary one I am pointing out in this context (and I do not know if he actually made this conclusion anyway) is that one cannot only analyze skimmate for DOC and properly conclude how much DOC is removed from an aquarium when the skimming process itself is expected (by me, at least) to convert DOC into POC. Yes, if you monitor DOC in the aquarium you can make such conclusions, but not from skimmate analysis.

 

[Graffiti Spot]

I have no links, but Dr. Holmes-Farley, in the past, has had a lot of disagreement with the Feldman study and assessment. Something about the testing method of the TOC in the skim mate vs. actual removal of organics is non sequitur. I forget all of the details, but he was strongly advising people not to believe that only 20-35% is accurate and that over time, a skimmer could get much, much more.

It might be worth the time to search his forum for this. It was very compelling and also matches up moreso with the bulk of hobbyist experiences.

I too keep multiple skimmers on my tanks (at least two in each) and have seen nothing but wonderful results. On one tank, I have a RO with the sicce PSK (their best skimmer ever, IMO) which pulls nasty junk. I also have a LifeReef which also pulls tons of nasty junk. If either goes offline, the other just does what it does - no more, no less. It is like the other one is not even there.

Also, keep in mind that once GAC get coated in organics, that it does not act like GAC anymore since the water can penetrate it.

Whenever I keep 200 gallons or more I always do this same thing. I will use a needle wheel skimmer and then another skimmer with a Mazzei injector. The mazzei injectors always produce a different color skim and much different foam. With the two combined I always had the best results and could feed much more than in any tank I have had just one skimmer on.
I only have 100 gallons right now so I am just using a mazzei injector hooked up to an old 3.5’ tall euro reef. I would bet most reefers would say that’s way to large of a skimmer. But it never stops skimming, and I do not feed much on this tank either. Maybe one or two pellet feedings each day with some pe mysis every now and then. If I would stop using vinegar, I think it might have some idle periods, again the neck size is what is most important with using large skimmers.

 

[Mortie31]

I have no links, but Dr. Holmes-Farley, in the past, has had a lot of disagreement with the Feldman study and assessment. Something about the testing method of the TOC in the skim mate vs. actual removal of organics is non sequitur. I forget all of the details, but he was strongly advising people not to believe that only 20-35% is accurate and that over time, a skimmer could get much, much more.

It might be worth the time to search his forum for this. It was very compelling and also matches up moreso with the bulk of hobbyist experiences.

I too keep multiple skimmers on my tanks (at least two in each) and have seen nothing but wonderful results. On one tank, I have a RO with the sicce PSK (their best skimmer ever, IMO) which pulls nasty junk. I also have a LifeReef which also pulls tons of nasty junk. If either goes offline, the other just does what it does - no more, no less. It is like the other one is not even there.

Also, keep in mind that once GAC get coated in organics, that it does not act like GAC anymore since the water can penetrate it.

Just searching on RHF and Feldman, skimming etc, there are a few results, but neither saying anything negative about Feldman... he even mentions GAC, so not sure where he was strongly recommending people not to believe Feldman.

No water change sps tank?

I can attest to the 2-3" of detrius...I helped move the tank...the sump was funky :confused: but man, that tank is proof that "funky" works!I missed that funk on purpose. Oh uh... I need to stay here and continue to catch fish. Why don't you guys take the sump to the new house?[emoji41]

www.reef2reef.com

Skimmer overkill?

Greetings everybody from the one and only UFO capital of the world!! So I was going to set up a 125 gallon tank but stuff happens and now I doing a 40 breeder with a 40gallon sump that it was going to be used for the 125 I had already bought a eshopps x 350 skimmer for the 125, I really don't...

www.reef2reef.com

 

[Mortie31]

I found one of them... in the SPS Forum Thread Here (post 128 in case this link does not work right). See, I told you all that my memory sucked since I cannot even get the forum right. In any case, read to post 141. There was another, but no quick luck searching gmail.

He links a very long peer-reviewed study that is a boring, but awesome read.

Regarding the 30%, it does not matter if a skimmer can get nearly all of the proteins before they become DOC.

I will search for another few minutes to find his comments when this study came up again... they blend very well with these and he offered some opinions more directly to take the Feldman study at arms-length whereas he just kinda implied it here.

This is the best line, for me (in post 141)... to each their own... Since Feldman relies almost exclusively on skim mate and another really smart guy says that you cannot...

Yes he’s saying DOC collects in the skimmer mainly as POC so unless you measure the POC + DOC in skimmate residue then you will end up with an incorrect reading of the makeup of the skimmate residue and you therefore cannot use skimmate residue measurement to measure tank DOC reduction, however you are missing the crucial part POC starts off as DOC in our tanks and Feldman also measured the TOC reduction in the tank water and that’s where he got the 30% from, not the skimmate residue...

 

[Mortie31]

Just found this real bun fight of a thread on oversize skimmers

Shut that Skimmer Down! Over skimming your tank.

My old eshoppes skimmer motor died for the second time, so I decided to buy a new larger skimmer al together. Through the five days I waited for my new skimmer to arrive I saw a substantial increase in polyp extension, especially my rainbow trachy. slowly. through accidents. these things prove...

www.reef2reef.com

 

[jda]

Read that academic article - it is really good, but I had to force myself through it.

The part that people miss is that the skimmer will get nearly all dissolved proteins on the front end as well as particles that are not testable as any of the components of TOC. If you want to factor in a back-end nitrate or phosphate rise without using a skimmer, it probably will be a lot more than 30% on the compound.

In the end, what does any of this matter? Nearly all of the best tanks that I have seen and know use oversized or multiple skimmers - this says something to me. This fad of higher N and P will soon pass like the many others that have come and go, so as long as people keep their residual levels where they want them to be, I guess that it does not matter how it gets there.

 

[Mortie31]

@jda @Ike A quote from Randy from this thread.. https://www.reef2reef.com/threads/shut-that-skimmer-down-over-skimming-your-tank.228048/page-30
I think I already agreed hundreds of posts ago that GAC was better at removing DOC. That is one of the few aspects of skimmers where there is some hard evidence, aside from aeration. The fact that GAC removes organics "better" doesn't mean skimming is not useful.

Reading through dozens of posts Randy has made, he doesn’t dispute Feldmans findings anywhere, he agrees with Feldman that GAC is more effective than skimming. And that most benefits of skimming are seen through aeration and that’s the reason he continues to run one..

 

[Mortie31]

Nearly all of the best tanks that I have seen and know use oversized or multiple skimmers - this says something to me. This fad of higher N and P will soon pass like the many others that have come and go, so as long as people keep their residual levels where they want them to be, I guess that it does not matter how it gets there.

But are they getting the results from the oversize skimmers? Science would say not, maybe it’s the massive aeration that they give that is of benefit rather than DOC removal, I don’t think there is much point carrying on this discussion as you see this very differently from me.

 

[Mortie31]

Read that academic article - it is really good, but I had to force myself through it.

Thanks...It’s a heavy read but just confirms the DOC to POC as I mentioned in post # 184 clarifying what RHF was discussing the sps thread we both posted. A skimmer will remove all/ most hydrophilic proteins such as albumin that is used in Feldmans Exp but as I showed in post #176 and the linked paper they only make up @50% of seawater...

 

[Ike]

Ike a lot of us have been doing this a long time, (there’s no need to be patronising) you have obviously had considerable success with your tank, that is undeniable, I do agree small diferences can and generally do make or break success. However where we differ is I’m looking for the science behind why we get the results we get and your going by your experience. As long as we personally end up with the system we want it doesn’t matter which approach we personally take. It’s upto others which route they choose but I will always point out the science especially when it contradicts what someone is offering as advice based on experience that can be read by everyone from beginners to seasoned veterans, it’s always good to debate these things. I don’t know if Feldmans findings are 100% correct or not, as no one can offer any proof or even rudimentary measurements to the contrary I’m going to stick to his findings. As this discussion is on DOC, as I pointed out in a previous post that you haven’t got back to me on yet, is that GAC is more effective than skimming at removing DOC’s and the natural bacterial processes in our tanks just as good.. so potentially by encouraging more beneficial bacteria that may be better than over sized skimmers...

I still have to read the articles and findings so I still can’t comment fully. I will say that one of the biggest issues with hobby interpretations of scientific articles is false conclusions that an experiment or study never intended.

The whole debate on this started because someone said, well, if there is a cap on the percentage of TOC that can be removed from an aquarium is capped, therefore skimmer size doesn't matter much. If Feldman made that conclusion then I don’t put much weight in his writing an conclusions. One of these days I’ll make the time to read it.

Also, was this a pier reviewed study? If not, there are plenty of scientists who have drawn false and incorrect conclusions only to be corrected when other scientists review their work.

 

[Mortie31]

I still have to read the articles and findings so I still can’t comment fully. I will say that one of the biggest issues with hobby interpretations of scientific articles is false conclusions that an experiment or study never intended.

The whole debate on this started because someone said, well, if there is a cap on the percentage of TOC that can be removed from an aquarium is capped, therefore skimmer size doesn't matter much. If Feldman made that conclusion then I don’t put much weight in his writing an conclusions. One of these days I’ll make the time to read it.

Also, was this a pier reviewed study? If not, there are plenty of scientists who have drawn false and incorrect conclusions only to be corrected when other scientists review their work.

So why did you post #174 this morning? Your trying to argue about something and you haven’t even read the articles!!! Maybe you should read them first and then answer your own questions and all of the other links provided discussing them, but then again don’t waste your time as you won’t agree with the results as they don’t match your extensive personal experience... and that seems to be all that matters to you

 

[jda]

I will never argue that GAC is not wonderful for removing organics. I will argue that constant use does require a massive amount of commitment, constant changing and a lot of work - most people will not do this over time. In as little as 3-7 days, the stuff is not effective anymore when it gets coated with organics and bacteria. If you assume the worst and use small amounts and change at three days, most people will fall behind. I would be shocked if you can "shake" off a coating of organics - the shaking is to expose different surfaces to the flow, so to speak since flow does get static in a reactor.

I also like to skim because of the metal removal that is bound to organics. GAC can do this too, but I don't run GAC very much and I would never be regimented enough to change it often. Gas exchange is good, but people overlook metal removal by a skimmer.

How about this one... I use three skimmers on one of my acropora tanks. Each skimmer gets 30%... so I am now at 90% removal. Pure science there. I am kidding about the science, but running more than one does not diminish the ability of the first one - they act in an additive nature. The reefers who rely on science and papers more than experience and even anecdotes of the best nearly always fail. I do like me some academia, but in the end, it is only just that. I will take the successes of the masses with the best-of-the-best tanks (subjective) and apply them to my own... most end up doing things nearly identically with only a few minor differences.

It has been a while since I read through your thread, but did you get your high nitrate issue figured out? I am pretty sure that my sand and rock would take care of almost any amount of nitrate that I could throw at them, but having multiple skimmers sure does seem to lessen the margin for error quite a bit. If you are still suffering with this, then give it a try... it is only a bit of sterling with nothing to else risk.

 

[Mortie31]

I will never argue that GAC is not wonderful for removing organics. I will argue that constant use does require a massive amount of commitment, constant changing and a lot of work - most people will not do this over time. In as little as 3-7 days, the stuff is not effective anymore when it gets coated with organics and bacteria. If you assume the worst and use small amounts and change at three days, most people will fall behind. I would be shocked if you can "shake" off a coating of organics - the shaking is to expose different surfaces to the flow, so to speak since flow does get static in a reactor.

I also like to skim because of the metal removal that is bound to organics. GAC can do this too, but I don't run GAC very much and I would never be regimented enough to change it often. Gas exchange is good, but people overlook metal removal by a skimmer.

How about this one... I use three skimmers on one of my acropora tanks. Each skimmer gets 30%... so I am now at 90% removal. Pure science there. I am kidding about the science, but running more than one does not diminish the ability of the first one - they act in an additive nature. The reefers who rely on science and papers more than experience and even anecdotes of the best nearly always fail. I do like me some academia, but in the end, it is only just that. I will take the successes of the masses with the best-of-the-best tanks (subjective) and apply them to my own... most end up doing things nearly identically with only a few minor differences.

It has been a while since I read through your thread, but did you get your high nitrate issue figured out? I am pretty sure that my sand and rock would take care of almost any amount of nitrate that I could throw at them, but having multiple skimmers sure does seem to lessen the margin for error quite a bit. If you are still suffering with this, then give it a try... it is only a bit of sterling with nothing to else risk.

I agree with you on nearly all of this, especially the metals etc, i agree unless I was to set up a Hiatt filter I couldn’t be bothered with GAC I highlighted it mainly as a comparator for a skimmers DOC performance I actually now use an oxydator to keep my water free form the yellowing, there great for oxidising organics.
I to look to other peoples experience but now check with the science, due to copying blindly in the past without understanding the rational fully.
I feel it’s important to try and understand why people are getting the results they do.. and discuss them as I feel it can only benefit us all, there are a few interesting threads going on at the moment on organics and N-DOC testing so over the next few years our knowledge may move further forward regarding levels.
In answer to your Nitrate question: there better, but still a little higher than I want, but my bio load has increased significantly. I’m halfway through transitioning to a large algae bed, and I’ve put a sand bed back in hated bare bottom. My levels are coming down after going more natural but still not where I want them, so in the next few weeks I’m fitting an external skimmer and doubling the size of my algae bed.. and in a real case of irony the skimmer I’ve bought is a Deltec sc2060 rated at twice my tank volume... lol, in my defence it was the smallest external skimmer I could buy in the UK that I could fit in my kitchen cupboard and drain back into my sump... (slightly embarrassing)

 

[jda]

I am all about blending experience with science/academia. However, when in question, I nearly always go on the side of hobbyist experience... but I choose the experiences well. In most well-known cases, the two line up pretty well and it is the hobbyist that is out of whack. I am talking about real science here, not manufacturer-made-up science (to sell a product), which rarely aligns with real science or else they would not have to have created an entity to fabricate their science.

Just in this case, you can read the Feldman stuff as you see fit, to fit any narrative. Some might see it as proof that skimmers are not necessary. I tend to side with what Dr. Holmes-Farley was saying that there are some serious underlying questions, mixed methodologies and uncertain outcomes constrained by limited equipment and testing ability. In one of his articles he certainly did try and ascertain tank drop by analyzing skimmate, but not in others - this makes them had to discuss too. Truth is surely in the middle, of which we will never likely know. My experience and the experience of my friends, who all do VERY well, say that if you have to lean, then lean towards skimmers being good at stuff, and more of them doing a better job.

Another one is the people who pointed out that SPS can get saturated in a few hours with light. They saw an article by Dana Riddle and he has a forum here, so it must be right, right?. It is right. It is right for Proites. It is not right for nearly any other SPS. ...so you can take this however you want to fit your narrative as well. Again, most people who do SPS well will not tell you that a few hours is enough light for the masses. Riddle was not wrong, people applied his study wrongly.

I once had a Eng Prof in college that said that he could commission a study that could prove that your Dad was your Mum and your Mum was your Dad. He thought that there was a 50% chance that it could make it through peer review. Smart Guy - never spent a day in College before he taught - had maybe close to 10 honorary doctorates from some of the best Engineering Schools in the US. I learned a lot from him about blending academia and the real world.