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Zephrant said:
The whole electron charge idea from a spinning, electrically isolated impellor is a bunch of bull. It fails the most basic believability tests- Electrons are not generated from scratch, the wheel can't be spinning off electrons without pulling them from some place, and there has been no measurements that indicate any kind of an electrical current is flowing in the motors, other than in the windings like any other motor. Any electrons magically coming from the (isolated) line in power would show up as leakage current, fail testing by UL and CSA (and the European counterparts), and trip a GFCI.

IMHO, I chose not to support manufacturers that generate reports of mythical like qualities and pseudo-physical properties to their products. If I can find a lie or gross exaggeration in one part of their documentation, it makes all of it suspect.


High energy imparted in to the flow means heat, nothing more. Considering the density of water, the heat imparted per cc is far too small to have any effect on the organics contained in that cc of water.

That is not to say that the Titanium impeller might not be great, and even better than a plastic one. Just that if it is, it has nothing to due with some electron spin gobbly-gook. :)

Perhaps some of the perceived efficiency is due to the impellor blades striking the same air volume numerous times- trashing the air, which would effectively disturb the surface of the bubble numerous times as it made its way though the blades.

While I tend to believe the reports that the titanium skims better than plastic, I'm a little skeptical too. Lets see some independent tests- Same skimmer, same tank, same impeller, just one titanium and one plastic. If I saw a few hobbyist that can claim they did that test, and they mostly agree that the titanium is better, than I would believe it more.

Then again, when you pay $800+ for a pump with a titanium impellor in it, you are bound to believe it is better, even before it hits the water. No-one likes to admit they may have paid more than required.


Mike- Thanks for the part numbers- It look like about $200 for a pump and air-stones. Not bad, but not as good as I was hoping.


Zeph


Sorry for the delay...got busy

A PDF reprint of the topic of Zeta Potential of charge in liquids. Don't totally discount the affect a little spinning metal wheel with pins it may have on particles in liquid and gas. There is plenty on the topic in any Google search.

Didn't you ever run around on new carpeting and touch your brother's nose to see the spark and hear him scream. What makes you not believe the same principles of static charge cannot be used in a solid liquid gas mix with high energy input.

Zeta Potential
 
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ldrhawke said:
What makes you not believe the same principles of static charge cannot be used in a solid liquid gas mix with high energy input. [/URL]

Energy does not equal electrical potential. Show me a possible electron migration path from some place, though the water and back again, and I'll be happy to discuss the effect of said electron motion on the water. So far I've not seen a proposed electron path that obeys the laws of physics, so suspect that it does not exist.

So I'll propose a path. :) If the spinning pins were magnetized, the resulting electromagnetic field might be strong enough to cause some interesting conditions.

As far as I know, Titanium would not have enough effect to create a significant magnetic field however.


Interesting thought though-

Zeph
 
Zephrant said:
Energy does not equal electrical potential. Show me a possible electron migration path from some place, though the water and back again, and I'll be happy to discuss the effect of said electron motion on the water. So far I've not seen a proposed electron path that obeys the laws of physics, so suspect that it does not exist.

So I'll propose a path. :) If the spinning pins were magnetized, the resulting electromagnetic field might be strong enough to cause some interesting conditions.

As far as I know, Titanium would not have enough effect to create a significant magnetic field however.


Interesting thought though-

Zeph

I don't think you read the pdf file I attached. I give up.
Curious though? Exactly what laws of Physics are you talking about?
 
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Great thread people... I should have checked it out earlier. I didn't get to throw in any of my own comments. Hehe. But now I'm going to throw this one out.

I think the comments that needlewheels produce the stinkiest skimmate may have some validity, but I think it is actually due to the process by which you produce those extra fine bubbles. First of all, you are beating the crap out of anything that passes through those pins so you are in effect thrashing everything into little bits and pieces so you'll be getting a lot of little critters and organisms and other detritus broken into smaller pieces and that will be more easily carried to the top and into the collection cup where due to the greater surface area:volume ratio of the detritus due to the thrashing, bacteria will have a much easier time of colonizing and breaking down said detritus into a very, very stinky mixture... so I think that maybe one way a needlewheel may be slightly more advantageous is that it can bash and thrash up anything that enters its deadly vortex which leaves you with smaller pieces to transport up to the cup. So, in essence you kill a lot of stuff, but you also tend to break up more stuff for easier transport up to the collection cup.

I'm not saying that venturis can't do this on some level, but I know that I've seen a few languishing amphipods in my beckett skimmer cup. Although to be fair, I've had a friend that has a euro-reef that had a clown goby pass through the teeth of death and end up in the collection cup of well. I don't know how badly he got beat up though as he was DOA. So, in essence I think it is a moot point to really compare the stinkiness factors, because of the way the bubbles are produced.

Also, measuring the residue of wet vs. dry is hard to do because you've also got to consider that you are still taking up salt water into the mix, so unless you've got a good way of separating out the gunk from the salt residue, I think that test would also be moot.

Peace,
John H.
 
I think skimmer that add alot of air to the system produce less stinky skimmate. The molecules that cause the odor are oxidized due to the massive amount of air passing over the skimmate. Kind of like a turned compost bin verus one not turned.

Adding ozone to the needlewheel skimmers makes the skimmate stinkless!!! You oxidize those stinky molecules.
 
Actually, accounting for the salt in the solid residue is not that difficult. If you know the volume of liquid, you can account for the amount of salt due to the salinity of the tank water (yes, this will be an approximation, but the actual error in assuming that the full volume of liquid is saltwater, and calculating the mass of salt from that is not that great.) Any remaining solid mass, after subtracting out the amount of salt in that volume of liquid skimmate is removed (skimmed) solids.

A greater problem is in accounting for volatile organics removed by skimming. They don't stay in the cup (at least my nose says they don't!).
 
Becket and downdraft skimmers put so much air into the water that h20 as a vapor comes out and condenses in the skimmer cup. If you check the refractive index you will see that it is less than your tank water!
 
I thought that organics lowered the refractive index? (or did I sleep through part of that lecture, and miss a negative sign? :) )
 
Organics will raise the amount of light refracted.
Maybe not all but probably 99%
The low refraction observed from becket or downdraft skimmate is the result of 100% humidity air pumping through the collection cup and out. the cup is cooler and condenses the vapor.
This can be checked with a salinity monitor too.
 
There are enough good minds in reef keeping that we should be able to come up with a method of testing and comparing any skimmers performance. The testing would need to be a simple so the potential for errors are reduced. A test that would end up with only a few performance numbers for comparative evaluation of any size or design skimmer.

The test would need to be fairly simple to do so that any skimmer mfg. or skimmer owner could also even use to evaluate their own skimmers performance if they wanted to compare.

As an example ( forget the numbers and the test methods they are just for explanation):

A 10 gallons container of salt water at a s.g of 1.025 to which is added a measured amount of organic waste or equivalent organic material.

The test skimmer is to be run for 1 hour and the collected material and the remains in the 10 gal container are both filtered through a lab. filter disk, oven dried at 150 F for 1 hour, and weighed on a lab scale.

The ratio of the material from the skimmer cup over the total of both the skimmer cup plus the balance in the container becomes a performance number or rating of between 0 and 1.0. The closer to 1.0 the better the performance.

We don't care about the flow rates in and out of the skimmer, nor the skimmer size or cost, as far as the test goes. Cost, size, energy, through put only come into play in the final selection analysis. The number generated should be a common one for any size or design skimmer.

I realize this is very simple and does not account for all variables, nor the volatiles lost, but it is a start and a basis for comparison. The mfg. with the best performing skimmers should jump at the opportunity if they felt it would make them look good and increase sales. If some sort of rating system started it would quickly catch on. It would also sort out the junk on the market.

:confused: comments
 
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I would like to see a specific fatty acid removal protocol. For instance a 10 carbon alaphatic fatty acid was removed from 10g/100 gallon water at X grams per hour.
I am sure the graph would not be linear but the first hour X amount was removed.
A simple test could be developed. The organic removed needs to be the same in all tests and the starting concentration..
 
So many intelligent people with egos to boot. Hehe. I wonder if my roommates would mind if I decided to bake fish poo in the oven. :)

Great ideas people, I just wish someone would do it.

Peace,
John H.
 
ldrhawke said:
I don't think you read the pdf file I attached. I give up.
Curious though? Exactly what laws of Physics are you talking about?

I guess I'll give up too. Your article talked about the effects of charging particles in a fluid, which is great. What you have failed to do is show how a titanium needle wheel effects that charge in a saltwater system.

Zeph
 
Zephrant said:
I guess I'll give up too. Your article talked about the effects of charging particles in a fluid, which is great. What you have failed to do is show how a titanium needle wheel effects that charge in a saltwater system.

Zeph
Getting down to the nitty gritty here I see. Regardless, I don't think if any, would that little peace of titanium would have any noticeable affects. The time wasted researching this wouldn't even benefit the performance of a skimmer regardless, otherwise they would use ceramic shafts (good Insulators also LOL) not to stir the pot ehh!
 
Hey good conversation folks. I dont see any egos hear just experenced reefers sharing thier knowledge and searching for the possibilities. Man with out that we would all still just have goldfish. Hobbists drive the hobby.

On the charging I can see the possibility that it may have an impact but I also dont think the T needle wheel is going to produce that. I also wonder if were going down the charged particle route would a skimmer even be require to impliment this?? would this be a stan alone unit, maybe simular to a tube filter??

Mike
 
Now Mike that is interesting, maybe not for a skimmer but some sort of inductive coil but now I think your barking up a chemical engineers territory on the eff effects on salt water reef & will this cause waste clumping or gathering lol, humm lol sounds wasteful!
 
How about this idea.....? Even Zephrant the Engineer should go along with it since it incorporates one of his Laws of Physics...specifically Faraday's law.

We wind the outside of the skimmer tube with fine wire. Feed the fish food loaded with iron filings. Now as the fish poop is pumped, the poop can act as an armature, as we get it spinning in the skimmer and and plug the coil into a 110 volt outlet We insert a propeller in the skimmer that is driven by the rotation and run a small generator to run the reef tanks power needs. Perpetual Motion and we even charge the fish poop so it can be skimmed...only need to keep feeding the fish. It's based on a Law of Physics, and even confirmed below. :lol:
 
Seriously, I know some of you want to simplify a rather complex micro world into little boxes to understand how things work; ie, 19th Century Laws of Physics can't be used to explain partlcle charge in the micro world using Coulomb's, Gauss', Amperes, and Faraday's law which do not apply.

As someone joked about using electricity to charge the waste particles before going through a skimmer. This is done in industry. Electrocoagulation and electroflocculation are two techniques involving the electrolytic addition of coagulating metal ions directly from sacrificial electrodes. These ions coagulate with pollutants in the water, in a similar manner that the addition of coagulating chemicals such as alum, lime, and ferric chloride, and allow the easier removal of the pollutants. I don't think the coral would appreciate this process.

Several have mentioned the addition of lime before a skimmer. Lime is a coagulent that changes particle charge. Thsi may have merit and improve skimmer efficiency, if it doesn't become a plating problem with the pumps and lines. It is worth doing more testing on.

The colloid stability we find in a reef tank is the stability of solids and suspensions. It can be interpreted by the same laws that apply to colloidal solutions. The aggregation of colloids is known as coagulation due to simple charged particle ions. The surface characteristics (extracellular polymeric substances (EPS), hydrophobicity and surface charge) and physical/chemical properties (size, density, chemical composition,bound water, and bubble charge) of the particles in suspension plays a significant role in how easy they are to remove.

Except under idealized lab conditions, colloid stability is a very complex issue. Several forces can operate between the colloids; some attractive, others repulsive. These forces may react in different ways upon variations in the conditions (pH, T, salt concentration, etc.) surrounding them. You must also consider the rate at which particle surface properties can alter relative to the rate at which two particles approach one another. Both static and dynamic properties are of significance.

The most frequently occurring forces between colloids are: van der Waalls forces, electrostatic forces, and forces due to adsorbed macromolecules. In addition, specific forces may act in special cases. For instance, magnetic colloid particles may attract each other magnetically or chemical bonds may be found between two colloids.

Some of these forces, such as van der Waals and electrostatic repulsion, have a long range. This implies that they can operate over several tens of nanometers. It is on this principle that the fundamental picture of colloid stability is based; solutions stabilized by electric repulsion between particles can be destabilized. Chemical bonds are short-range, and therefore can only come into operation if there are no other forces keeping approaching particles apart.

The attraction between particles in a liquid depends on collisions between particles, caused by their relative motion. This relative motion may be caused by Brownian movement, by fluid movement giving rise to velocity gradients, or by particle motion due to an external force (e.g. gravity).

When I was talking about energy input it meant the collision frequency induced by the relative motion from pumping flow rates and pressure, not an electrical current as a motor would use. This charge is caused by Brownian movement, it is called perikinetic . That which is caused by orthokinetic velocity gradients. If there is no surface repulsion between the particles, then every collision leads to aggregation and the process is called flocculation. If a significant repulsion exists, then only a fraction of the collisions results in aggregation. This is called slow flocculation.

A special case of orthokinetic flocculation which may be occuring in a large sump is is easier explained as a floc blanket occurs in a sewage trreatment plant clarifier. In addition to the fluidized bed giving rise to velocity gradients, the fluidized particles are participating in the process of agglomeration. If particles are settling at different velocities, then the faster settling particles may collide with slower settling particles, leading to aggregation. The aggregates will then settle faster due to their increased mass, and possibly experience further collisions and aggregations.

Compared with floc formation through perikinetic and orthokinetic mechanisms, floc may breakup in a skimmer. The effects of small bubbles and pump agitated systems like a skimmer is much more qualitative and speculative. The size and shape of the microparticles, and number and strength of the bonds at microparticle contacts and bubble can all be expected to contribute to floc structure formed and the ability to withstand disruption by fluid forces.

When salt is dissolve in water, dissociation into constituent ions occurs and the ions may take part in various reactions with water or with other solutes present. The nature of the resulting aqueous species largely determines the effect of the added salt on colloid stability.

Colloidal particles are usually charged and this charge is frequently responsible for their stability. Basically, the salts can affect this stability in two ways: through their effect on the extent of the diffuse layer around the particles and by their "specific"effect on the electric potential controlling colloid stability. This directly affects the bubble particle attraction inside a skimmer.

In short, we have a lot to learn about improving a skimmers performance and the separtion process occuring inside a skimmer has nothing to due with Faraday's law as some would like to have us believe. Does a titanium or plastic impellor add or remove charge, I have no idea, but I wouldn't totally discount it either. These are just my thoughts. And to think before I went to college I couldn't even spel ungineer, now I are one. :)
 
ldrhawke said:
How about this idea.....? Even Zephrant the Engineer should go along with it since it incorporates one of his Laws of Physics...specifically Faraday's law.

We wind the outside of the skimmer tube with fine wire. Feed the fish food loaded with iron filings. Now as the fish poop is pumped, the poop can act as an armature, as we get it spinning in the skimmer and and plug the coil into a 110 volt outlet We insert a propeller in the skimmer that is driven by the rotation and run a small generator to run the reef tanks power needs. Perpetual Motion and we even charge the fish poop so it can be skimmed...only need to keep feeding the fish. It's based on a Law of Physics, and even confirmed below. :lol:
Better apply some type of monomer coating to those iron filings so they don't oxidize into a non-magnetic state before they get to the skimmer!
 

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