my diy needle wheel dart pump

[Sparkss]

<a href=showthread.php?s=&postid=7150383#post7150383 target=_blank>Originally posted</a> by trmiv
I just can't wait to see this thing fired up. The pics you had earlier of th bubbles this pump is churning out was awesome. It made my Deltec jealous.

My Deltec is still sobbing quietly in the corner after seeing those pictures

 

[Travis]

Bill, you are making my BK look like a Sea Clone.:lol: Very impessive work. I can't wait to see some pictures of that monster in action.

 

[Bill Wann]

The top flange is just about finished , I need the cone back so i can cut it to th eexact od and make the bolt holes , It is recessed so th etube goes in about 3/8 of an inch and has a 1/4 oring groove .

 

[spazz]

did your care package ever show up in the mail??? if so honest thoughts??? should it be thicker acrylic for that size cup??? i didnt know you were going with that tall of a cup. thats alot of weight on that twist lock. i tried to call you. energy has a question for you.

 

[Roland Jacques]

Bill, you mentioned in another thread (BK defuser thread) that you added a defuser to a skimmer and it tripled your skimmate, was it the same design as this one. maybe you have a photo of your old skimmer. this is much better than anything you could have bought. cant wait to see it running.

 

[Bill Wann]

I did that on a 18 diameter rk2 skimmer . It made it work alot better .
The problem with that skimmer is the water is introduced at the top so its very turbulant and it uses a venturi which make too large of bubbles .

 

[dgasmd]

Bill:

I am surprised you say that it worked well in the RK2. I always thought this diffuser plate business was a bunch of hog wash, but I guess I am being proven wrong once again. Maybe I can adapt one too somehow to my existing skimmer.

Is that new skimmer running yet??

 

[spazz]

<a href=showthread.php?s=&postid=7155003#post7155003 target=_blank>Originally posted</a> by dgasmd
Bill:

I am surprised you say that it worked well in the RK2. I always thought this diffuser plate business was a bunch of hog wash, but I guess I am being proven wrong once again. Maybe I can adapt one too somehow to my existing skimmer.

Is that new skimmer running yet??

the defusr plates are a good thing for any recirculating skimmer. it helps to reduce turbulance in the main chamber. the less turbulance the easer it is for the doc's to stay connected to the air bubbles. for your tall skmmer it would be hard to make a defuser plate for that. because the entire bottom of the skimmer would have to be rebuilt to accomidate the new plate and plumbing. but it could be done. the other thing you have to rember is the rk2 uses a pressure feed pump to draw in the air. it makes alot of turbulance in the skimmer. the defuser plate reduces that to an accaptable level.but the way the rk2 is built it has a pipe that goes down to the bottom of the skimmer from the top of the skimmer. this causes the tiny bubbles to break and combine inside that pipe. so the exiting bubbles are way too big. his new skimmer should look like you just dumped 10 gallons of milk in with the salt water.

 

[jnarowe]

Interesting Scott...so putting a pipe from my input (top) down to a diffuser plate won't work for me either right?

 

[spazz]

<a href=showthread.php?s=&postid=7156404#post7156404 target=_blank>Originally posted</a> by jnarowe
Interesting Scott...so putting a pipe from my input (top) down to a diffuser plate won't work for me either right?

no no thats a totaly different ball game there. if you were to install a dart needle wheel on your skimmer then it would work just like the defuser plate on bills skimmer. i think you would want to install fittings for the incomming water like bill has them. drawing in dirty water with the clean water into the pump. that way it all goes through the defuser plate and gets mixed together. but your skimmer is 12" tube if i remember right. and making a defuser for that would require alot smaller defuser area. so it would need to be taller so it does not get too violent in the defuser area and spray out the bubbles from the defuser. if it did that it would defeat the pourpse of the defuser. thats whe bill has over 1000 holes in his defuser. there will be that much flow through that plate. so to "defuse" the incomming foam you need a bigger surface area. that would be the problem in a nut shell with your skimmer.

 

[spuzio]

When the input of dirty water and the output of cleaned water are both below the diffuser plate, only the bubbles are flowing up through the diffuser plate, however, the volume will remain constant above the diffuser. As a result, there will be no water exchange between top and bottom part of the skimmer. Am i missing something with this design? With that design wont all the DOC need to stick to the bubbles below the diffuser where it is most turbulent?

 

[spazz]

<a href=showthread.php?s=&postid=7156724#post7156724 target=_blank>Originally posted</a> by spuzio
When the input of dirty water and the output of cleaned water are both below the diffuser plate, only the bubbles are flowing up through the diffuser plate, however, the volume will remain constant above the diffuser. As a result, there will be no water exchange between top and bottom part of the skimmer. Am i missing something with this design? With that design wont all the DOC need to stick to the bubbles below the diffuser where it is most turbulent?

the defuser plate area is like a smaller chamber inside the skimmer. the dirty water can exit out the sides. it has to go up through the top holes. it mixes with the clean water in the pump. then is mixed with air, then chopped up by the needle wheel and injected into the defuser area. once its pushed out of the defuser area it will be nice and calm. the mixture of dirty water and bubbles are all going up. this makes a calm upward current inside the skimmer. the doc's are ataching to the buibbles at this point. now you will still see a slow current inside the skimmer body. you want that. that gives you a better dwell time for the doc's to attach to the bubbles. all the defuser does is removes the strong currents caused by the jet blasts comming out of the needle wheel pumps.

 

[Bill Wann]

The dirty water and the cleaned water mix befor entering the nw pump .

 

[spuzio]

I guess my main question would be... what would the exchange rate of the water above the diffuser plater? The same as the flow through rate of the skimmer or less?

 

[Bill Wann]

It would be the same as the water entering the skimmer plus what ever is recurculated from below .

 

[spuzio]

I can understand the the exchange rate below the diffuser plate to be close to that number, however, the only thing that is forcing dirty water into the top chamber is the bubble flow up. However, with the large enough amount of bubbles flowing through the diffuser, it may actually cause a large enough exchange rate above the diffuser plate.

 

[Bill Wann]

Lookat the plumbing on the , All of th incoming water will be sent through th edifuser plate after being mixed with recurculated water and the sent up the tube , There is no way for th eincoming water to go right into the outlet pipe .

 

[spuzio]

Ok maybe i am addressing this incorrectly, but what is pushing the water through the diffuser plate? If a pump input and output are both below the diffuser plate and you inject no air, then there should be minimal flow through your diffuser plate. There is no pressure differential to cause the water in the bottom to flow to the top section. , or vica versa.

 

[spazz]

<a href=showthread.php?s=&postid=7156978#post7156978 target=_blank>Originally posted</a> by spuzio
Ok maybe i am addressing this incorrectly, but what is pushing the water through the diffuser plate? If a pump input and output are both below the diffuser plate and you inject no air, then there should be minimal flow through your diffuser plate. There is no pressure differential to cause the water in the bottom to flow to the top section. , or vica versa.

the intake for the pump is not hooked to the defuser plate. look at the pics he posted. the intakes for the pumps sit befow the defuser plate in a box that is sealed from the defuser plate.

 

[spuzio]

I finally see it. The diffuser is closed off. In the photos i though the bottom box was open into the diffusion area. With it being closed off it will cause flow in the main chamber. Thanks SPAZZ and Bill in answering my questions!