Bored! So lets design a Skimmer!

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Mike this sounds like a fun project first of all!

I think the first thing you mentioned is dwell time, I think before we can build a better skimmer we need to understand how to increase dwell time, so how can this be improved?:tape2:

I have a few ideas to throw out, IMO to get more dwell time you can go Taller certainly but most people have limited height in a stand. How about maybe a series of baffles to slow the air bubble rise?
You can also go Cone to focus more air bubbles into a tighter area but does that increase dwell time, maybe increasing the height?

So how else can we increase dwell time significantly?:puke:
 
LOL great folks I love the enthusiasm!!!

But lets take a step backwards here and go over a few things first. Most of the modren skimmers that are on the market these days (so Becketts, needle wheels, venturi's and so on) dont follow the laws and principles that govern skmmering or at least the skimming of protiens/nutrients. Because of this they end up not skimming what we want but instead they skim biologicals like bacteria, plant & animal plankton and similar.

So why would we want to copy a skimming design that we knows doesnt meet the standards??and thus doesnt skim what we want but instead skims materials that we want to keep in our tanks??? We can do much better then that if we put our heads together.

SO take a moment and read the link in the first post I made. In the mean time lets look at a skimmer and see how it works or doesnt and that should help us find the targets we need to hit. So Guerry are you up for being a test subject?? I say that because your skimmer is like a peice of art to me, very fine workmanship!! Lets run some numbers on it and see how it works?? Anyone who is following this thread can do the same tests on theirs to see how it is performing.

So if your up to it Guerry here is test number one.

> So because we know through science that protiens attached to raw water molecules need to cleaved off and then chemically attached to a clean air bubble takes an ammount of time (some up to two minutes) we need to achieve an amount of Dwell time air and dwell time water. So this should be an easy test to figure out on your skimmer. How much time does the water in your skimmer spend in your skimmers mixing chamber in order to achieve this??
>gallons of water the skimmer holds divided by the gph running through it?? So how many seconds or mintues does it spend in their??


Scootie lets step back for a moment


Mojo
 
SO take a moment and read the link in the first post I made. In the mean time lets look at a skimmer and see how it works or doesnt and that should help us find the targets we need to hit. So Guerry are you up for being a test subject?? I say that because your skimmer is like a peice of art to me, very fine workmanship!! Lets run some numbers on it and see how it works?? Anyone who is following this thread can do the same tests on theirs to see how it is performing.

So if your up to it Guerry here is test number one.

> So because we know through science that protiens attached to raw water molecules need to cleaved off and then chemically attached to a clean air bubble takes an ammount of time (some up to two minutes) we need to achieve an amount of Dwell time air and dwell time water. So this should be an easy test to figure out on your skimmer. How much time does the water in your skimmer spend in your skimmers mixing chamber in order to achieve this??
>gallons of water the skimmer holds divided by the gph running through it?? So how many seconds or mintues does it spend in their??


Scootie lets step back for a moment


Mojo

how to calculate this with a recirc? The criteria for volume processed per day is this based on Escobals model?
 
sorry, another question. the foam head at the top of the skimmer is more static than say down at the exit, if the turbulence in the skimmer was equal top and bottom it just wouldn't be efficient so how is say the top 1/4 of the skimmer calculated for dwell?
 
how to calculate this with a recirc? The criteria for volume processed per day is this based on Escobals model?

The recirc wouldnt apply right?? If the water is recircing that would dictate water being treated. The time frame we are looking for is dictated by the ammount of time the water spends in the mixing chamber. Escobals model are basically calculations so yes they would pertain in finding the numbers but the process are biological so they dictate. That make sence? So with a basic understanding that some molecules will be drawn to the air/water interface and some will be repulsed, that some will have portions of themselves attracted and othe portion the opposite. Then you have to mix in the ones that need to be broken down in order to get more that will be attracted. You could write a paper on this and I am sure many have. So as a hobbist we need to simplify this to some kind of bottom line, the bottom line is that it takes TIME for organics to diffuse/bind/attach/seperate and then attach to the water/air interface. Now the exact time is not a known thing, but we know that it does not happen in a split second. so we go to the formula to do the math and see where we are at.

I dont know if that clears things up or makes them a bit more cloudy, but their it is, lol

Mojo
 
Guerry, Your skimmer is relevant to my interests and I would like to sign up for your newsletter. Perhaps we should move over to a DIY Beckett thread to limit the annoyance to Mike.

Could you please list the pump model and provide a full skimmer image? I like the Beckett foam jet but like the idea of recirculation so that all the tank water makes a pass. I like the lower power consumption and noise of a pinwheel or needle wheel.
 
Perhaps we should move over to a DIY Beckett thread to limit the annoyance to Mike.

By all means go for a diy thread if you want, but their is no annoyance on my side Kraken. What gave you that impression?
 
By all means go for a diy thread if you want, but their is no annoyance on my side Kraken. What gave you that impression?

I need help with the skimmer in post 14 sitting in my garage. This is boring conventionally stuff so I don't want to distract the thread with a discussion of a DIY skimmer with Guerry when you really want to try something new.

I have requested Pedro Ramon Escobal: Aquatic systems engineering : devices and how they function from the library and will give it a read. At the moment I am working with biopellets and live rock to increase the bacteria load to assimilate nutrients with the skimmer as the primary means of export. In the skim mate I see tea colored water with flecks of nuisance algae and bacterial flocks adhered to the side. I would be worried about loosing the convenient (if artificial) export step if I was ONLY targeting DOC.
 
No problem Kraken, but remember Escobar's equations are just used to figure out the time frame, not the reason. One thig you might also want to dig into is the action/reaction of materials both organic and inorganic (as inorganics will not adhere to a water/air surface). That and when it comes to inorganics you could simply remove them with anything from a syphon to a turkey baster to a sock and so on.


Mojo
 
I'd be glad to take part in anything to further our hobby, to answer first ? on flow I'm using a BlueLine 55 pump presure rated at 1100 gph. Supply side of pump has 4' of spa flex 1" hose with one 90 so head loss is very small. Return pump to tank is also BL 55 pump and overflows drain to bubble trap area in sump which is where suction side of pumps bulkhead is located, this being said skimmer should be seeing aleast 95% of all water returning to sump. My reason for going with becket design was so that I wouldn't being stripping my trace elments and micro bac. from the water as it is said to happen with needle wheel type skimmers

so first test dwell time, my best guess of water in skimmer at any given time is 3gal divided by 1100 = 366.6 divided by 60 = 6.11 gal a min. so dwell time 30sec.
now if I unstand this right, that would also be the reason that a becket style skimmer isn't stripping the water of all the good things that make our coral grow
 
Thanks Guerry, I am doing this to kind of see what we are up against. The one reason that a fast moving skimmer like a beckett or similar would remove what we call good biologicals is that it kind of creates a frieght train of a foam column and the biologicals get caught up in it. Anyway lets look at the numbers then.

So 3 gallons divided by 1100gph = .0027 * 60 (for minutes) = .162 * 60 (for seconds) = 9.72 seconds?? right
 
The recirc wouldnt apply right?? If the water is recircing that would dictate water being treated. The time frame we are looking for is dictated by the ammount of time the water spends in the mixing chamber.

Mojo

That was my point, if the pump is drawing water from the body, adding some more air and dumping it back into the body its a loop? could go through the pump several times, unless you consider the pump destroying any clinging mystery matter attached to the bubbles ie. turbulance
 
So basically your looking into how to increase air to water dwell time correct? I wonder if making a coil type setup that ends in a vertical chamber would increase the time enough. Or am I going way off of the spectrum here?
 
That was my point, if the pump is drawing water from the body, adding some more air and dumping it back into the body its a loop? could go through the pump several times, unless you consider the pump destroying any clinging mystery matter attached to the bubbles ie. turbulance
Yea I agree! lol I think thats is where we are going to end up if we cant get the numbers any other way. I would imagine their would be some bubble destruction going through the pump a few times, but perhaps we can design that out.



I wonder if making a coil type setup that ends in a vertical chamber would increase the time enough. Or am I going way off of the spectrum here?
I think coil type system might not hold the ammount of water we want to treat at any given time??


Mojo
 
I may be mistaken but I think your math is wrong 1100 divided by 3=366.6667 or am I doing something wrong here?
 
brain flash! the most confusing skimmer I ever stored pennies! in the Berlin Classick (lol along if ya had one) it had a triple bypass thingie, foam went up,down and up again, that idea Ive never seen developed further, it certainly would add dwell time, maybe combined with multiple bubble plates damn you and your skimmer threads, I promised! but the itch is starting to grow
 
Guerry here is the formula to convert gph to gps you have to take gph and * .0002778. So in your case 1100 *.0002778 = .30558 gallons per second. So that would mean that in about 3 second you would pump 1 gallon, so if the skimmer is 3 gallons then it would take around 9 to 10 seconds?? but back check that as I could be lost to, lol

Sasquach didnt we talk about chemical enhancements??


Mojo
 
Guerry here is the formula to convert gph to gps you have to take gph and * .0002778. So in your case 1100 *.0002778 = .30558 gallons per second. So that would mean that in about 3 second you would pump 1 gallon, so if the skimmer is 3 gallons then it would take around 9 to 10 seconds?? but back check that as I could be lost to, lol

Sasquach didnt we talk about chemical enhancements??


Mojo

no? should we? Geritol might be good who knows, do I have to expound further on this theory?
 
ok got it, I under stand the math now and see you're correct. so how does this expain why a becket design strips less micro bac. and trace elements from the water. I know for fact that since I changed to becket design from needle wheel that I dose less potassium to maitain a 400ppm level yet skimmate collection is near the same per week.I'm trying to get a full under standing of cause and effect so that I maybe able to to give better input for a improved design and contibute more to what this thread is really about
 

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