5' Skimmer Build in Progress

[jnarowe]

tinygiants Interesting text on that page. I never found any CFM info on the Luft pump. That's why I called Coralife. Their air pump page shows all of them but no CFM on the Luft. They are all re-branded just like many light fixtures, tanks, etc.

.15 CFM is not what the tech told me and certainly will not be sufficient. Oh well, we'll see. Maybe this thread will point me to a better pump!

 

[tinygiants]

<a href=showthread.php?s=&postid=6401840#post6401840 target=_blank>Originally posted</a> by jnarowe
tinygiants Interesting text on that page. I never found any CFM info on the Luft pump. That's why I called Coralife. Their air pump page shows all of them but no CFM on the Luft. They are all re-branded just like many light fixtures, tanks, etc.

.15 CFM is not what the tech told me and certainly will not be sufficient. Oh well, we'll see. Maybe this thread will point me to a better pump!

The Coralife Luft Pump produces a high-pressure output 7.0 P.S.I. and 4.0 L.P.M. with a quiet operation. Ideal for high-resistance and multiple-output applications. Perfect for protein skimmers, ozone/oxygen reactors and other high-pressure/high-flow devices. Also suitable for limewood and other airstones, foam filters, corner filters, under-gravel filters and air-driven ornaments, even in deep-water applications. The Luft pump features a rheostat control to regulate pressure and flow rate.

This is the paragraph I got it from. It says 4.0 L.P.M. That is 4 liters per minute. The conversion for that is .15 cfm. It says 7.0 PSI and 4.0 lpm. Can it do 4.0 lpm at 7 psi? In my case, .15 cfm is not adequate.

Dale

 

[jnarowe]

You are absolutely correct. Looks like I'll need to get another pump. 12 x 12 x 5' is a lot of water to fill with bubbles!

 

[tinygiants]

Here it is installed. The feed flowmeter is behind the bubble riser.

I am still fighting with bubbles in my feed water. I will install my vent valve when it comes in, but it may not solve the problem.

I will have to wait for my float switches and relay before I try any valve adjustments. Last time I tried that, I slowed down the drain slower than the feed. I was in the basement. So after an hour of clean up, I ordered the stuff to make a failsafe.

Dale

 

[jnarowe]

Nice growth in the fuge!

 

[tinygiants]

<a href=showthread.php?s=&postid=6402203#post6402203 target=_blank>Originally posted</a> by jnarowe
You are absolutely correct. Looks like I'll need to get another pump. 12 x 12 x 5' is a lot of water to fill with bubbles!

It all depends on bubble size and rise rate. If you get tiny bubbles that rise slowly, it does not take as much air.

Crazzyreefer came up with 3 cm/s as a rise rate. I never did find that info, and I was unable to extract that number from the refference material he cited. I seemed to find 30 cm/s (~11 ") when I read the material. And my own measurement does not support that. I am getting about 6.5 inches/sec. In any case, when my new stones get in, the bubble is smaller and rises slower, then I need less air.

If the bubble stays in the tube longer, then it takes fewer of them to make up for the lost ones. The calculator does this calculation.

Dale

 

[tinygiants]

<a href=showthread.php?s=&postid=6400553#post6400553 target=_blank>Originally posted</a> by BeanAnimal
Do you happen to have an SPL meter (cheap at rat shack ... hint hint). I am curoius to as to the actual sound level of some of these pumps.

Have you updated the spreadsheet with any of yuor new information?

Sorry, no SPL meter, and no intention to get one. The Whitewater is way to noisy to put in my tank stand. The Sweetwater Air Pumps are claimed to be silent.

The only real info that I am getting is bubble rise rate. I have that as a user defined variable. Each installation will vary with bubble size. As for my formulas, I can not validate them yet. My bubble rise rate is so fast that the counter current is having no noticeable impact on bubble dwell time. The good news is that mathematicly my calculator predicted that it would be negligable after I entered the base rise rate.

The current Rev of the calculator is updated with air pump calculations. I ordered the wrong air pump at first. I ordered one that can not overcome the pressure at the needed CFM. The calculator will now calculate the head pressure to evercome as well as the CFM needed to maintain 13%. The only problem is you need to know how your bubbles are going to rise inorder to get that info. Had I known that my bubbles would rise at 6.5 inces/second, I could have ordered the right pump from the start. Also I failed to properly compensate for the air stone backpressure. The calculator now does this as well.

Dale

 

[BeanAnimal]

I am looking at both the sweatwater and alita pumps. They look to be the same darn thing actually. They are listed at around 40 db.

I will be trying the fine pore stones from sweatwater. I do want to order the smallest air pump possible, as they get expensive real quick. The SL14 may not be enough, and that is $200.

I looked but may have missed what stones areze was using. He is not happy with his bubble size if I remember correctly.

 

[tinygiants]

<a href=showthread.php?s=&postid=6402423#post6402423 target=_blank>Originally posted</a> by BeanAnimal

I looked but may have missed what stones areze was using. He is not happy with his bubble size if I remember correctly.

areze said he thought he had the fine pore stones, but when he looked at the catalog they looked like the regular ones.

I will be able to test fine pore stones this comming week. I ordered the ALR80 stones from Aquatic Eco.

I will post my results when I get them in and tested. Work kicks into overdrive starting next week, it may slow down my progress.

Dale

 

[jnarowe]

QUIT WORK!

 

[tinygiants]

<a href=showthread.php?s=&postid=6402264#post6402264 target=_blank>Originally posted</a> by jnarowe
Nice growth in the fuge!

Thanks.

I harvest about every 2 weeks. My pod population is comming along. I hope to add a Mandarin this year.

Do you shop at The Shark Reef? I am a kitsap local.

Dale

 

[jnarowe]

No I don't. I have had two experiences there that were intollerable. The owner has tried to make nice with me since I posted on RF about it but I am quite happy doing business with Mario at Ocean Reef Aquatics. If you are local, you have GOT to come by and check out what I am doing!!!

I am around most of the time so PM me and we'll set something up. I would love to have another reefer come over and trade info. tools, etc.

 

[areze]

I had posted my bubble size back in this thread I think... think it was in this thread. with photos.

they are just a long shot from "microbubbles" that we all know and love whenever one of our pumps grabs a stray bubble.

in my not so scientific testing Ive noticed an "air lift" effect with the bubbles, essentially the bubbles are forming a circular flow in a chamber by rising up the center, actually creating an updraft within the downdraft, and amplifying the flow at the perimiter. thus the downdraft is doing nothing to slow the bubble flow. there is of course a small percentage of bubbles that fall out of the updraft and are pushed back down, but all in all its a small volume.

I am beginning to now wonder if the counter current design actually has ANY merit at all... but Ive done everything but actually attempt to skim so far. and as they say the proof is in the pudding. so tomorrow my GHETTO(I emphasize that because I cut the design short to minimize wasted acrylic if this doesnt show any promise) skimmer should be running and we'll see what happens when its put into action.

then on tuesday my maxijet 900 comes, and Ill try some other ideas.

 

[areze]

btw anyone notice the tang up top is smokin a pipe? wonder how that would effect a skimmer?

 

[crazzyreefer]

the published work is located at this site http://www.seas.ucla.edu/stenstro/NewBubble.pdf

it states that a buble rise rate is between 28-30 cm and larger bubles are at 35-40 cm, also Mojo stones are sweetwater fine pore stones, (I have them)

wasnt their a theread about the harmfull effects of that black rubber being used?

Dale looks great. sorry I have been bussy to even look at the board, as for wood diffusers, there is a reason that people gave up on them, they just dont last, and as they diteriate the pore size and output changes.

Lastly is the work done by UCLA correct?... dont know, will have to test it to find out. the calculator is based on this number if its wrong than the whole design is also wrong.

the object is to get the bubble to remain in contact with the water for 120 seconds, not less, and in a non-turbulent flow. anything less that that will not skim all the organics and metals. having a bubble contact for more than 120 seconds will only maximze the removal prcess, the amount of air is not to exceed 13% less is ok, past this number bubbles combine to make larger bubbles.

when a bubble dose not have suficent form time (less than 120 seconds) the bubble will only collect some on the organics and metal, further it has a greater chance of bursting in the foam chamber, as they burst in foam chamber, they coat the walls of the chamber and make the skimmer less productive. a proper design should relieve all the associated problems with store bought models, including cleaning and removal of all organics and metals and trace elements, leaving only pure SW behind. This process is utalized in waste water facillitys and has been proven. the unfortunate part of this is that the skimmer needs to be at least 20 feet tall or a counter current model that only slows down a bubble.

 

[tinygiants]

Where did the 3 cm/s come from?

 

[piercho]

I am a kitsap local

Well this is weird. My company is Northrop Grumman and we make the launch tubes for the SSBNs, and the MACs for the SSBN->SSGN conversion boats. I live in Bremerton, work from the Engineering Services Building on Bangor. I also work on the subs at Delta Pier (IMF), and on the SSBN 730 backfit project at PSNS. So its possible that we've crossed paths.

Dale and Jonathan, I have two Medo AC602 linear piston air pumps mounted in a box for parallel output, that's about 3 CFM at 5'. The input air is HEPA filtered. I'm not using them at the moment. I've also got a manifold setup with two 3/8" needle-valve controlled outputs. If you want to play with a lot of air, I can bring the setup over some time. PM me for my business email and home phone.

Been away from the house for over 2 weeks. Anxious to get back and see how the tank is making it.

 

[BeanAnimal]

Can I have a look at the latest spreadsheet build. I may be able to help you clean it up a bit also.

 

[tinygiants]

Here it is.

 

[tinygiants]

Crazzyreefer,

the bubble rise is at 1.17 or 3cm Clean... 2cm when its bonded with organics, so it throws another wrench in the mix, this is the whole piont, we dont want just clean bubbles to rise, so the 120 rule is also out the window... sorry, now the bubble still needs 120 seconds, but as it collects organics and oils, it will slow down, so if its a counter current model and it it slows down 1/3 of the rise rate the bubble will not enter the foam area.

This is a post from the skimming principals thread. I questioned the 3 cm/s in that thread because of the line in the UCLA paper saying 28 - 30.

In the end though 28 - 30 is not representative of my findings either. My numbers (with my medium bubbles) are closer to 20 cm/s as the bubble rise in standing saltwater.

Is there another refference I am missing that got you to 3 cm/s?