Side by Side Skimmers?

[BeanAnimal]

If the current skimmer is good enough or oversized, you might actually get WORSE skimming because now you have two oversized skimmers competing for a small amount of material (leading to very poor performance of both).

I don't think it could be any "worse" with regard to quality of the water column. A skimmers effectiveness is not a product of the amount of organic material in the water. If one skimmer removes the "hard to get" organics, that does not have a negative effect on the second skimmer, it just means the the second skimmer does not have to remove those compounds itself.

Think of it this way... your skimmer is an M&M remover, each color M&M has different properties that make it more or less attacted to the remover...

Brown = Super easy
Yellow = easy
Green = not so easy
Red = not so hard
Orange = hard
Blue = super hard

It follows that a single skimmer will likely remove disolved organics in proportion to their concentration the ease in which they are removed.

Contact time is reported to be a significant factor in the harder to remove substances (in our case orange and blue). If both skimmers are exactly the same, then they will both remove the same ration of orange and blue M&M's but at the same time will also be remove the much easier to attack brown, yellow, green and red. If the brown is all gone, then neither skimmer has to worry about removing it, etc. You in effect have a skimmer that has more capacity to remove the same compounds. No harm done, you just have more skimming capacity than before. That is, if one skimmer sucks out all the yellow M&M's that does not mean the other skimmer is unable to continue with green, red etc. It will continue to remove whatever its design allows it to remove.

As for efficiency with regard to power consumed, that would differ by example

If the skimmers are different with regard to the effectiveness at removing compounds, then it follows that each skimmer will remove more of what it is good at. While both skimmers may remove the brown, yellow, green and red M&M's only one of them may even be capable of removing the blue and orange M&M's. You in effect have created a larger skimmer that has a broader range of compounds that it can remove.

 

[DrHarryLopez]

I don't think it could be any "worse" with regard to quality of the water column. A skimmers effectiveness is not a product of the amount of organic material in the water. If one skimmer removes the "hard to get" organics, that does not have a negative effect on the second skimmer, it just means the the second skimmer does not have to remove those compounds itself.

Think of it this way... your skimmer is an M&M remover, each color M&M has different properties that make it more or less attacted to the remover...

Brown = Super easy
Yellow = easy
Green = not so easy
Red = not so hard
Orange = hard
Blue = super hard

It follows that a single skimmer will likely remove disolved organics in proportion to their concentration the ease in which they are removed.

Contact time is reported to be a significant factor in the harder to remove substances (in our case orange and blue). If both skimmers are exactly the same, then they will both remove the same ration of orange and blue M&M's but at the same time will also be remove the much easier to attack brown, yellow, green and red. If the brown is all gone, then neither skimmer has to worry about removing it, etc. You in effect have a skimmer that has more capacity to remove the same compounds. No harm done, you just have more skimming capacity than before. That is, if one skimmer sucks out all the yellow M&M's that does not mean the other skimmer is unable to continue with green, red etc. It will continue to remove whatever its design allows it to remove.

As for efficiency with regard to power consumed, that would differ by example

If the skimmers are different with regard to the effectiveness at removing compounds, then it follows that each skimmer will remove more of what it is good at. While both skimmers may remove the brown, yellow, green and red M&M's only one of them may even be capable of removing the blue and orange M&M's. You in effect have created a larger skimmer that has a broader range of compounds that it can remove.

Very true skimmer one removes very dry dark brown skimmate while skimmer two's skimmate is a little more wet.

I aggree with BeanAnimal.

 

[RokleM]

I don't think it could be any "worse" with regard to quality of the water column.

I agree and this wasn't what I was implying.

A skimmers effectiveness is not a product of the amount of organic material in the water.

A point that could be argued dependent on what your definition of effectiveness is (also validated by your comments prior). "Effective" to many hobbyists is that it's set and forget, removes material on a regular basis, and trouble free. Scientific effectiveness is that it's fine tuned to remove the maximum amount of organic material out of the water column regardless of what it takes maintenance wise to do so. Hopefully you see where I'm going with this. My point was that if you already have an "oversized" skimmer that adding a second (especially of the same type/model) may not yield any better combined results between the two. Skimmers do indeed need a certain amount of organic material to be user friendly, and if starved can be more difficult to fine tune for the general hobbyist, heavier buildup in the neck vs cup, require more maintenance, etc.

I see your points, but not where I was trying to go with it The end result is the fact very few of us have a really good scientific way to determine how well our skimmers are working in terms of organics left in the water column. If you think you're oversized already, adding another likely will not yield a great benefit if any at all, and actually possibly make it quite a bit more difficult to setup and maintain. However, some have "proven" (per say in a best effort non scientific way) that dual skimmers can indeed work well on a system if sized properly.

 

[BeanAnimal]

Thanks for the response... I was just tossing in some food (no pun) for thought.

I would agree that there is no easy (if any) way to really quantify the effectiveness of a skimmer. I would say the same for "overskimming", as each system is different and what may be desired results for one person may be "overskimming" for another.

If I were to make a general asumption, it would be that running two skimmers of different make or style would be of more benefit than running two skimmers of the same make. If two skimmers of the same make are run together, then it would be logical to run them under different operating settings (dry and wet for example).

 

[jbanks]

Nice to see a local reefer right next door.. I'm in Laurelton.. Very interesting thread..

 

[poolkeeper1]

2 X XP5000 Cones

2 X XP5000 Cones

I run dual SROs (same model) and have found it superior in every way to just running one. I believe that 2 undersized skimmers will almost always out perform one over sized skimmer with lower energy consumption (depending on pumps used) on identical/same systems.

DJ

650gal tank 120gal sump and a pair of Super Octo XP5000 Cone Skimmers!
And they both pull equal amounts of gunk on a weekly basis. I was not sure how this would work but it does just fine.
Actually the owner of this system has a third XP5000 still in the Box ready for action if needed, Plus he bought my Vertex IN250 WBB3000 for his 150gal Quarantine tank. They all are working to perfection! Just my 2 cents
Bill

 

[kma408]

thanks, very nice tank

 

[canyousee]

This is what I love about RC here we are asking is 2 skimmers better than one on nine ball thread they are talking about no skimmers or buy a cheap one and use the extra money you save on other better options to reduce TOC.

 

[DJREEF]

This is what I love about RC here we are asking is 2 skimmers better than one on nine ball thread they are talking about no skimmers or buy a cheap one and use the extra money you save on other better options to reduce TOC.

What other better options?

DJ

 

[canyousee]

Thread at large tank builds, coral tank Canada check it out for much more detail.Basically following Tullock "less technology,more biology" and Ron Shimek's work showing skimmers remove about 20% of TOC with no real difference between a 1200.00 skimmer and a 120.00 one. In summery better use of Ozone,GAC,Mechanical Filters,Extra system volume( 55 gallon drums) and water changes. I find it interesting how many ways there are to keep a reef system.

 

[DJREEF]

Thread at large tank builds, coral tank Canada check it out for much more detail.Basically following Tullock "less technology,more biology" and Ron Shimek's work showing skimmers remove about 20% of TOC with no real difference between a 1200.00 skimmer and a 120.00 one. In summery better use of Ozone,GAC,Mechanical Filters,Extra system volume( 55 gallon drums) and water changes. I find it interesting how many ways there are to keep a reef system.

OK. I see. I paid about $500 for both of mine, and honestly couldn't see how larger water changes would be anymore economical long term than having to do the 10gal changes per week that I do now on my 115 FOWLR setup. I use the other principals mentioned, as well, but I'll tell anyone the same thing - quality skimming makes a difference.

DJ

 

[canyousee]

Dr. not trying to hijack your wonderful thread you asked your question because has a scientist some things/ statements don't add up.That's why I wanted to add this.
It seems science has not really caught up to allot a the basic practices expound on in these threads.

 

[DrHarryLopez]

Dr. not trying to hijack your wonderful thread you asked your question because has a scientist some things/ statements don't add up.That's why I wanted to add this.
It seems science has not really caught up to allot a the basic practices expound on in these threads.

Cool bro no problem.

 

[canyousee]

I agree with you, yet if you do all the above how do you Know what practice or technology is doing the most. I would love to see a study where several tanks where set up exactly the same with only one variable,that being removal of TOC and take readings and see what really works the best. Yes I am too anal.

 

[DrHarryLopez]

many of us around!

 

[BeanAnimal]

canyousee...

The problem is that the test would only be valid for THAT set of circumstances.

Skimming and water changes remove different compounds (or course there is overlap). In the same fashion the rate of skimming and skimmer settings change the type and ratio of compounds removed.

Furthermore, the rate of water changes (or skimming if it could be measured with 100% accuracy) will not just affect the dilution of the said compounds from a pure mathematical standpoint. In other words, if I have a 10,000 gallon tank with 10% red dye, I can tell you mathematically EXACTLY what ANY water change schedule will do to the die concentration. With organics, things become infinity complex, as the organics we are trying to remove interact with the mass of other stuff in the tank. Changing 10 gallons a day vs 20 gallons every other day may have VASTLY different effects on what is absorbed, transformed, precipitated or compounded. Therefore, what is skimmed or removed in a water change will be different.

From any realistic standpoint, our best measure of how well a method is working is the real world health of the livestock. Comparing a method on tank A to that on tank B (even if they are similar) is comparing apples and oranges, as is trying to quantify how good one method is vs another method.

 

[canyousee]

Yes BeanAnimal I agree yet sitting in my comfy chair enjoying my Honduran cigar I often think if some one can get a government grant to study the sex lives of fruit flies I should get a grant to set up several tanks and give the reefing world something close to real science LOL.

 

[streak]

Yes BeanAnimal I agree yet sitting in my comfy chair enjoying my Honduran cigar I often think if some one can get a government grant to study the sex lives of fruit flies I should get a grant to set up several tanks and give the reefing world something close to real science LOL.

Ok i read threw the whole post and no one mention the fact that some of the skimmers have recirculating pumps which seem to up the volume of skimming by X amount to even some of the modest of skimmers and all the other variables of skimmer x with mesh or skimmer y with pinwheel vinturi and or even the ones i read with up to a 7psi air pump added?? So many variables. I dont have my DT up and running yet the skimmer i got is off brand it says for 300g i dont belive it.. but im real handy and i saw the rec pump mod and thought i might be able to get some life outa this skimmer even though im only going to be using this on a 200+ gal system total max.

Ohh about the fruit flys let me dig out my Chi Square ill get right on it!! LMAO!!! You remind me of my college days!

 

[t4zalews]

I've been recently running a Euro Reef RS-80 and a Reef Octopus XP-1000sss on my 65 gallon sps. I find that the octopus tends to be a little touchy but when its running its really good at pulling out gunk. The euro reef tends to be more resilient and pulls out the fines a lot better.

 

[dancewithethan]

I've been recently running a Euro Reef RS-80 and a Reef Octopus XP-1000sss on my 65 gallon sps. I find that the octopus tends to be a little touchy but when its running its really good at pulling out gunk. The euro reef tends to be more resilient and pulls out the fines a lot better.

Taylor

My first skimmer was also Euro Reef. That skimmer reminded of an old Russian MIG fighter, it just works, No if, and, or but.