Is it possible to overskim a reeftank?

[jmaneyapanda]

Straegen- I guess this is the only point I need to make. It appears to me the basis of your argument is that when a skimmer is oversized, and works so well, an even larger skimmer wouldn't work better, because there is nothing "extra" in the water to pull out. My point is- this is only true if you claim the skimmer is taking out 100%. If you think the skimmer is taking out 99%, there is still 1% present. And as the skimmer get larger = greater effeciency, it will get closer to that 100% value. As I said, the difference may be very small, but it is still there. Again, I am not arguing value or bang for buck, but just true, emprirical data. Just for the record, I dont think the percentage are really acurate, otherwise many tanks would be extraordinarily nutreint starved, but they work for this hypothetical example.

I, perhaps, got a little caught up in the debate. I was under the impression at the beginning of this thread that you were arguing a "properly" sized skimmer would pull out no less skimmer than an "oversized". I disagree with this. But, if we are in agreement that this statment is not true, I can (finally) shut up. I'll have to look at the early posts to get my stories staright.

 

[kwl1763]

Besides the mindblowing length of this thread and the largely academic debate that is taking place (which I try to avoid) .

You haven't answered the fundamental question of how good is good enough and is better neccessarily removing more. At some point you hit the dimenshing return point on line that is asymtotic to 100% removal so theoretically you could never have to big but there is some point that it's not "worth it". Couls be 99% could be 90%, copuld be 99.99999%. But does removing 99.9% of the organics vs removing 99% really matter to growth rates, health, etc. No one knows to be honest. In fact it would require a very controlled test because it's only one factor in a myriad of other affecting health (light, food, calcium, alk, other chemicals, etc, etc, etc.)

To get back to the original question I think it was more a question of can the water be possibly to clean through skimming (forget the size for now). This is a very debatable subject. My view is stated earlier. It depends on the type of animal to be sure but yes I have had a tank that was to clean. I had to feed like crazy and up bioload for the corals to thrive. I think that happens less than 0.1% of the time though and I know for sure that most softies grow better in slightly "dirty" water. Clams definitly do better with the nitrates and pyhto at detectable levels, etc. so it all depends on what your trying to do. SPS tanks I will say it's almost impossible to have to clean but it can be done.

Bottom line is you can't ignore the cost/efficiency optimization point. Properly sized is really the point you minimize energy and running costs but maximize the point your animals are healthy. Where incremental removal of more is of such little value it's not worth it. Surely you see at some point in the real world you probably reach a limit fairly quickly. Meaning that on a "normal bioload" 20G tank if you put a skimmer rated for a 100G tank and on a duplicate 20G tank put another skimmer by the same manufacturer (to keep ratings consistant) for 300G I doubt you would see appreciable difference in the health of you animals on the "more skimmed" tank. Maybe you are removing more but who cares!

 

[cameron]

And with the last two posts... I really will quite down on this subject so long as we are all in agreement that you should buy an appropriately sized, quality skimmer if you are going to actually do skimming.

Oh and I am sorry to have hijacked this thread... hope it didn't scare off the original poster.

 

[jmaneyapanda]

Kwl- I agree, this discussion got spun way out of wack, but I do feel strongly about making arguments I feel are true. But anyway...

To answer the question of how good is good enough- My point, as expressed through my argument, is there is no such thing. There is no empirical number that can be produced to say- "OK, Ive reached the skimmer saturation rate". It is a constant and evolving process, which, in my mind cant be done enough.

Do I think it's possible to overskim a tank- yes. But I think a very small fraction of a percentage actually have the hardware and husbandry to meet these terms. I think the vast vast majority of the aquarist out there runs their tanks with excess nutrients floating in the water. Which means these tanks are being run underskimmed (in a practical sense). In regards to your comments about the needs of clams (nitrates and phyto), I would disgaree. From the research I have found, I have seen no evidence to indicate such. Clams do ingest and filterfeed, but the claim that they need detectable nitrate levels and phyto is unfounded. In fact, I can likely show you a long list of people who do not feed phyto, and have zero nitrate, yet have clams thrive like none other.

Cost/effeciency point is such a moot point to discuss, though. What I will spend on a skimmer is not pertinent, nor helpful, to what others will, because we all have different budgets and economics. You say that incremental removal wouldn't be worth it? It would to me. Because bioload can and will fluctuate constantly, and I know a larger skimmer can and will handle it. Your example of a 20 gallon with the 2 skimmers- my point is, if you are willing to buy the larger of the two, why not? It will work better in nearly every single scenario. What if that 20 gallon has spontaneous die-off of 50% of the life in their, so the bioload has just increased exponentially. Which skimmer would you bank on now?

I would recommend to nearly everyone to buy a skimmer as large as they can, functionally and economically. Unless we're talking a nano with a deltec hooked up, I doubt it would become overskimmed. But to say better perfomance isn't pertinent is this specific example, I think is an shortcoming. On something that (arguably) can't be overdone, How is the better performing item not the choice to make (economics aside)?

 

[cameron]

jmaneyapanda wrote: I would recommend to nearly everyone to buy a skimmer as large as they can, functionally and economically. Unless we're talking a nano with a deltec hooked up, I doubt it would become overskimmed. But to say better perfomance isn't pertinent is this specific example, I think is an shortcoming. On something that (arguably) can't be overdone, How is the better performing item not the choice to make (economics aside)?

Economics aside and speaking just to someone asking "what skimmer I should get for my 55 gallon?"... get a good quality skimmer that is sized appropriately. A DelTec, Tunze, EuroReef, ASM and several others have a great reputation. Pick one they recommend for you bio-load. You will have less heat, likely less noise, the water quality will be more than fine and a smaller footprint under you cabinet (assuming that is where it is going). If you have a 200 gallon with everything running to the basement, you probably know better than I which skimmer to get.

Keep in mind people run successful aquariums with no skimming at all. Also, bigger is not always better. Quality counts for a lot when it comes to practically any kind of equipment.

Done - out -fin

 

[broreefr]

DAMM Good Thread with a healthy debate, now thats why we have this forum. If I may I want to throw my 8 1/2 cents in ~ in case I'm wrong always refer to my signature. LOL

Anyway I have three skimmers running on my system now. Two coralife and I got what is SUPPOSED to be the next best thing sinced sliced bread, a Euro-reef as well, I have seen tall ones and large skimmers at work, and two me they all seem to have the same basic principle; injecting micro-bubbles into the salt water columm which produces foam and blowing it up a tube. Since trash particles float in salt water, they are blown to the top where they eventually overflow or stick to the side of the collection cup.

The Euro-reef and a coralife run side by side (pic at bottom) and there are times when they will foam beautifully clear bubbles for hours, but shortly after feeding when the fish poop or what may not have gotten eaten hits the skimmers away they go. One really doesnt outshine the other, its just bigger.

Now we all know that normal evaporated water should be replaced with regular RODI water, but I believe that as long as we replace the amount of water skimmed from the collection cup with "salt water" I dont see "overskimming as ever becoming an issue

 

[jmaneyapanda]

I'm really not trying to be argumentative, really, Im not, but I disagree. This is just my perosnal opinion, others will tell you otherwise, but I dont hink people should run marine tanks without skimmers. People do, and have no problems, but I dont understand why they don't. The benefits SO outweigh the potential drawbacks, in my mind at least.
If someone asks me what skimmer they should get for their 55 gallon tank, I will offer some manufacturers, such as MRC or similar, and tell them to get one that is most practical for them, but under the guise that the bigger they go, the better they will be off. That would be my advice. Since overskimming is likely not going to be an issue, there is no reason not to (economics aside). That is my honest opinion. The drawbacks of heat, noise, and similar should be considered, but in my mind, they do not match up with peformance and water quality.

A question I have for whoever is- is your water too clean? If so, plug your ears. If not, do you know what will help? A more effecient skimmer. That is what I think the bottom line is.

 

[kwl1763]

You know what they say about opinions!! Seriously I'll just agree to disagree. You think bigger is always better, I say there is a practical limitation, so be it. And yes there is research that clams do better (I never said they require it) with detectable nitrates and when fed phyto. They do both in the clam farms overseas. Run a softy tank with a little nutrients and one thats super skimmed and see what grows faster. Been there done it.

My question would be is your water clean enough! I don't want to be to the to clean point. Been there and done that twice now.

Plugging my ears now

 

[jmaneyapanda]

Kwl-

I dont disagree with the reasonings you give, but questions the methods to get there. How do gets a skimmer to leave only a "little" nutrients. Like I said, some people can run a tank wonderfully without a skimmer. Good for them. But, if someone wants a skimmer to pull out organics, there is no way to say this one will be "just right", and only leave enough for the corals to grow. By like we said, we all have different opinions.

Regarding clams, please direct me to the source where it says clams do better with detectable nitrate and phyto. And, while I agree some clam farms may add some amazing concontions to their systems, I really can't emphasize enough to not treat your tank like a clam farm raceway in SE Asia. They operate entirely different from you. Where did you find that they add phyto? I love being proved wrong, so let me know eher I can find this information. Thanks.:thumbs:

 

[cameron]

Someone break out the guitar... I think we need a round of Kumbaya and calm this ruckus down.

 

[jmaneyapanda]

I think we are all diagreeing on good terms. I just love to get new information. When someone has some that I haven't seen, I really get the itch to read it. Particulrly if it contradicts something Ive known to be true. So, I am looking forwrad to the refernces.

 

[cameron]

I love a good debate especially when the material is fresh in my mind. I have been reading aquarium detritus articles that last few nights and know WAY too much about decomposition of nutrient matter. Hopefully it will purge itself as I try and devour the latest coral care books that washed up on my doorstep today.