New Skimmer – Price is no Object!

[JCTewks]

yeah, the back button got me this time I usually copy long reply's...but forgot to this time.

Bean, would you say a 3" neck is enough for this skimmer?

I've also been tossing around the idea of a tll skimmer without a neck so to speak. just a 6" diameter body, 6-7'tall 2000lph of air. no reduced neck diameter though...just a collection cup the same diameter as the body on a flange that will attach to the body. Do you think that will cause too much turnulence from the air?

 

[BeanAnimal]

I am not one to ask about neck size. I think the neck on my skimmer is too narrow (4" if I remember) and possibly too tall.

It should lessen the turbulance, but you may have trouble getting a good strong foam head to support itself.

However, that BK mini looks almost like it has no neck.

 

[hahnmeister]

<a href=showthread.php?s=&postid=10725117#post10725117 target=_blank>Originally posted</a> by BeanAnimal
Hahn, have you looked at the spreadsheet? The 13% number is pretty hard to achive.... I don't think even the dart NW thread saw numbers above 12% or so. I could be wrong.

Have you read the Escobal explanation of the 13%?

I have read that book, but dont own it myself. I found some place that had it listed on their site still... suppose I should call up and order it.

I just remembering reading it, thinking about circumstances where this 13% just wouldnt apply, and chalking it up as something that was just impossible use as a 'benchmark'.

 

[BeanAnimal]

http://bublos.com/cgi4/bub.compare.cgi?isbn=1888381051&geog=usd&tmr=10

Got $300?

 

[hahnmeister]

Forget that... Ill get the book xeroxed before I do that.

 

[BeanAnimal]

Don't forget to send me the PDF

I can't find my copy... Along with my HVAC book and some others...

 

[pjf]

<a href=showthread.php?s=&postid=10727024#post10727024 target=_blank>Originally posted</a> by JCTewks
I've also been tossing around the idea of a tll skimmer without a neck so to speak. just a 6" diameter body, 6-7'tall 2000lph of air. no reduced neck diameter though...just a collection cup the same diameter as the body on a flange that will attach to the body. Do you think that will cause too much turnulence from the air?

I've been think along the same lines. Per Escobal, I only need a 4" to 5" diameter skimmer for 75 gph of flow. With a 75-gph wetneck, the foam passageway is already effectively reduced.

Thanks for trying to get the links to me and for your offer to help with the threadwheel!

 

[BeanAnimal]

Yes, but also remember that Escobal made his comments regarding skimmers based on the assumption that they would have 48" or more of reaction chamber height.

 

[GuySmilie]

Re: Wetneck Inlet

Re: Wetneck Inlet

<a href=showthread.php?s=&postid=10726673#post10726673 target=_blank>Originally posted</a> by pjf
If you have links to detailed wetneck designs, that will be great!

http://tinyurl.com/2yrktv

If this doesn't automatically open the PDF document, click on the AP Series Skimmers Instructions.pdf link.

 

[pjf]

Wetneck

Wetneck

Deltec's "self cleaning head" (http://www.deltecusa.us/docs/APSeries.pdf) is quite complex and does not appear to be a wetneck. I was think more along these lines of this drawing that I found on "Andy's Reef Aquarium Blog" (http://reef.eldersign.org/?p=110):

Here's a couple of quotes from kentrob11 about his CNC wetneck design (http://www.reefcentral.com/forums/showthread.php?s=&threadid=966407):

Wetneck:

This is an idea I have to give Spazz total credit for. His wetneck designs really caught my attention since I am lazy and don’t like to have to clean the skimmer neck all the time to get it to work properly so I incorporated it into my design. The neck of the skimmer is 5 ¼” OD and the outer tube used for the wetneck is 6” OD. I decided that for structural rigidity and aesthetics, I would feed the wetneck from the bottom instead of the side so I drilled two small holes on either side of the bottom end of the neck and used 2 part epoxy to place two barbed fittings into the holes. Tubing spans from these fittings to a guest style union between the wetneck assembly and the skimmer feed for easy removal of the collection cup.

One thing I was a little worried about was crud getting trapped inside the wetneck chamber since the height gap between the two is so tiny. There really isn’t anyway to get something out if it gets stuck inside. I decided the best way to address this was a removable wetneck top so I designed one that incorporated a viton O-ring seated in a groove inside of the cap so that it sealed properly when pushed down over the wetneck. I went back to my CNC guy with the drawing and once again, he came through for me big time! I used a couple of razor blades to gap the cap so there is just enough room for water to cascade over the edge of the neck and it works perfectly, regardless of whether the skimmer is level or not.

The wetneck really causes the foam to shoot up the neck and keeps the neck clean to boot. Aside from taking the top of the collection cup for a quick spray down once a week or so, I didn’t have to touch the skimmer for over a month and the thing kept skimming like a champ. Thos with high end skimmers know what I’m talking about there- Your neck gets gunked up, ya gotta clean it or skimmer productivity degrades.

The idea is to make sure the wetneck assists the foam in reaching the collection cup and does not hinder it. Again from kentrob11:

I'll have to keep an eye out on that with mine then. The wetneck id ingenius that's for sure. One thing to keep in mind is that one a larger skimmer, the neck needs to be longer or the water level lower if a wetneck is going to be used. The foam really shoots up the neck with it and I found that if I ran the wetneck with the same flowthrough and water level as without it, I got a collection cup full of water pretty quick.

kentrob11's wetneck can be dismantled for cleaning. Unfortunately, I don't have pictures of kentrob11's design and am having a rough time figuring out what he implemented based on his description. I also wonder if a 75gph flow rate is possible through a wetneck.

 

[pjf]

The disadvantage of Andy's wetneck design is that it requires a water feed into the collection cup assembly. I am not sure how kentrob11's design overcomes that.

 

[BeanAnimal]

Han could you please provide more information about the 1262.

I would like to explore my options and get rid of this ocean runner. I hate it.

 

[pjf]

Wetneck Flowrate

Wetneck Flowrate

What are typical flowrates for a wetneck inlet?
Is 75-gph realistic for a 4" to 5" neck?

75-gph is what my Eheim 1046 generates through a 3/8" tube for my media reactor.

 

[pjf]

Airstones

Airstones

<a href=showthread.php?s=&postid=10712898#post10712898 target=_blank>Originally posted</a> by BeanAnimal
I went with an RC 7' tall beast. I had started making it a CC airstone skimmer, but chickened out due to the nightmare of building easily serviceable stones into and at the same time not turning it into a Rube Goldberg project.

Did you consider "Fine Pore Oxygen & Ozone Diffusers" from Aquatic Eco Systems (http://www.aquaticeco.com/index.cfm/fuseaction/listings.categories/ssid/398)?

 

[hahnmeister]

Re: Re: Wetneck Inlet

Re: Re: Wetneck Inlet

<a href=showthread.php?s=&postid=10728083#post10728083 target=_blank>Originally posted</a> by GuySmilie
http://tinyurl.com/2yrktv

If this doesn't automatically open the PDF document, click on the AP Series Skimmers Instructions.pdf link.

Thats not a wetneck, thats a SCH or self-cleaning head... a bit different.

As far as sizing goes, wetnecks do need to be about 20-25" larger in diameter compared to regular. Otherwise, the foam has a tendency to 'shoot' up way too fast. As to why... could be many things, but the lack of friction on the side walls of the neck is very likely. So rather than a 4" neck with a 900lph eheim, people use a 5" or even 6" wetneck on those.

 

[hahnmeister]

As for the 1262... you can just buy one for $130 at most places. There is no getting around that. Then, the needlewheel from ER is $100, and the volute is another $48... so in the end, its just as cost effective to get the ER pump for $250. Then again, its not like their venturi is even close to 'ideal'. I was able to make a better venturi than what they sent me with a 3/4" MPT-1"slip adapter, 1"slip-3/4" slip bushing, the 3/4" PVC and 1/2" PVC... much like the Sicce PSK venturis I put together. The impeller is the hard part to get around. The stock impeller is $80 from eheim parts, so its a matter of sacrificing the one that the eheim comes with, and hoping you can bond a disk on to it strong enough... or, do what I did and just buy another ER pinwheel for $100, cut the pins off, drill the disk, and add your own mesh. Of course, your skimmer might be well enough with just the needlewheel since that can easily take 1000lph and then some for air mixing. So I suppose the pump and needlewheel are all you really need. I suppose you dont even need the venturi either since you are force feeding. Still... its a $130 pump, and then a needlewheel for $100, or sacrificing the stock impeller. In my case, I didnt want to give up the stock impeller... so I spent the money.

Anyways, you might also consider the Aquabee or Sicce pumps. The Quiet One 3000 is the same pump in almost every way to the Sicce PSK 2500... 40 watts, same impeller design, same volute cover, same impeller well diameter and depth... except it has a 1" MPT outlet, and the Sicce has a 3/4" FPT. Its an easy pump to get for $40-50. Its not as quiet as an eheim I suppose, but its alright... way better than the OR.

Otherwise, you may also consider the Aquabee 2000/1, which might actually be a good match for the skimmer with force feeding. A stock 2000/1 does 500lph, and threadwheel versions can do up to 720lph. So a force fed threadwheel... you should get that 900-1000lph mark pretty easily. And its a $110 pump through DAS (orca or petorama). I havent meshed an Aquabee 2000/1 myself though yet, so I dont know.

 

[GuySmilie]

So the purpose of a 'wetneck' is to 'lubricate' the wall of the acrylic collection pipe so the foam/protein mixture does not come in direct contact with the plastic? I always assumed the purpose of a wetneck was to clean the tube to facilitate easier lift of the foam.

Hmmm, maybe I'll actually learn something today.

 

[BeanAnimal]

Re: Airstones

Re: Airstones

<a href=showthread.php?s=&postid=10731310#post10731310 target=_blank>Originally posted</a> by pjf
Did you consider "Fine Pore Oxygen & Ozone Diffusers" from Aquatic Eco Systems (http://www.aquaticeco.com/index.cfm/fuseaction/listings.categories/ssid/398)?

They Oxygen diffusers require a lot more pressure than one can easily deliver at volume in an aquarium setup. They would be ideal, but would be next to impossible (noisy and constly) to drive.

 

[BeanAnimal]

I need a lot more air... and I need a lot more quiet. So $230 or so for the NW pump huh. That kind of sucks. Why not just buy the $130 and hack the stock impeller? I am sure they are a LOT cheaper than buying the pinwheel. Is the volute extension much different? Is it something that could be DIYed?

 

[hahnmeister]

The volute is the same, only they bond the venturi on. I can post a pic, but take my word for it... its identical to the stock eheim beyond the venturi. The venturi isnt anything to write home about though. I dont even use it... I use my own and get better performance.

As for just hacking up the stock impeller... well... I touched on that. Lets just put it this way, it costs $80 by itself, and it isnt the easiest impeller to mod. In my case, I just figured it to be easier to buy the ER needlewheel and cut off the pins. Its $100, but well worth it.

FWIW, look at someone elses method of modding the stock impeller...
http://www.sgreefclub.com/forum/index.php?showtopic=51267&st=15
I dont know about you, but I wouldnt trust that plastic to bond long term... or be as quiet. Just me though. I just dont think its that easy of an impeller to mod in the first place... not unless you overbuild it or something. I just think its one oft those cases where DIY would have a hard time matching OEM. By the time you get a disk that is strong enough, and make a large enough bonding surface, you cut into the volute volume, and your air intake. I dont see the same performance coming from anything but a one-piece molded unit, you know? That disk needs to be large in diameter yet thin and light... can you DIY that? The best I came up with was to try using a tap&die and threading the shaft for nylon bolts/washers, and seeing if you could go without a support/backer disk by just compressing the PF4 in place between a couple nuts and washers... but being that I wanted to keep my stock impeller for possible return pump duty at some point... I figured why not just fork over the $100.