Can airstone driven skimmers be simply converted to venturi ?

[Gary Majchrzak]

I'm helping a friend that wants to improve a skimmer he has.Is converting an airstone driven skimmer as simple as slapping a venturi intake on the thing?
{Perhaps a bigger water pump would also be required, right?}

[Spanky]

Gary you're right.

Now my question, why?

A well designed air driven CC will perform as well or better than a venturi/becket.

[Gary Majchrzak]

Spanky, thanks for the quick reply!

I guess some folks like to waste time and money, as I {already} personally asked him "why"?....

[Doug1]

But Spanks arent the really efficient CC air powered skimmers usually quite tall and and move a lot of water thru them , as well as require a large volume air pump. I had thought that the venturi, ect skimmers evolved to produce the results of the large air driven in a lot less space

[Spanky]

What was his answer?? LOL

Oops! two great minds posting at the same time.

I think it has more to do with dwell time, the air CC's having more with less turbulence. The venturis and beckets will turn the tank volume over more per hour and that will make up for some of the difference.

On really large systems I really like a combination of both. Because they will actually pull different quantities of different things.

[Gary Majchrzak]

Thanks for the in depth info on skimmers, guys.I know venturi type skimmers are good for restricted height applications, but my buddy has unlimited room for his skimmer- it's behind a wall and in the washroom.I'm advising him against spending money on the 'upgrade'.
Are you familiar with "You always want what you don't have?" or, more appropriately:
"The algae is always greener on the other side"?

[Doug1]

BOY HOWDY

[CNCreefer]

I have been thinking about converting my red sea berlin airlift skimmer to a beckett type but after reading these posts I don't think it would make a difference.

A well designed air driven CC will perform as well or better than a venturi/becket.

That being said, how would you increase the effiency of an air driven skimmer? This skimmer works alright, it's on a 20 gal, long, but I think it could work a little better.I was thinking about making it longer, I have room for about 6 more inches between the bottom of the skimmer and the sand bed.

[Doug1]

Most of the productive CC skimmers are quite tall(4') and have multiple airwoods located at the bottom, requiring air pumps capable of driving large volumes of air under lots of pressure. Needless to say these types are a lot more expensive than typical aquarium pumps.
It the high volume of micro bubbles raising up through the tall column with a slow flow of water down, that gives the needed dwell time for the thing to work.
The venturi and Beckett skimmers are designed to produce copiuous quantities of foam and hopefully achieve the same leve of production in a more compact space.
The small inexpensive air lift skimmers like the Lee's and a few others aren't in the same class, due to size and volume limitations. The Picilo(sp) is a small airlift thats favored on nano tanks but most of the others arent as efficient as a smaller venturi skimmer

[Spanky]

Si Senor!

A while back we had a round table about this very thing. Me, Frank Marini, Doug Lowey, Mike (Precision Marine), Andy, George, GregT, oh alright it was a bunch of us.

Anywho, we all came to the conclusion that injectors like some venturis and all beckets (if you run them on a strong enough pump) reach a sort of supersaturation point right at the point of injection, partly due to the pressure differences. That any dwell time after that is actually not needed and all the fractionation that is going to happen, has.

Difference being, a longer dwell and less turbulence will allow a more complex organic/protein to fractionate or in other words - it allows them to have time to form a more elastic and stable interface.

I'm talking out of my hat - did you catch it?

[Gary Majchrzak]

Soooo....if the pump on MY venturi skimmer {Lifereef 24"} ever fails...
I can expect increased performance by replacing it with a larger pump.....?

[Spanky]

We voted me as the test case! don't ask.

Anywho, on the Bullet3 I changed the input to the becket to 1" (instead of 3/4") and fired it up with a Iwaki 70 (it was on a Iwaki 40). Also, Doug suggested raising the becket above the skimmer.

Bottom line, it improved the skimmer several times over.

I don't know if all this would apply to a venturi though. Even though beckets and verturis work on the same principle, we figured that beckets needed a bigger/stronger pump. And they did.

[Green Chromis]

Spanky, what was the purpose of putting the beckett above the skimmer instead of above the water level in the skimmer column?

[galleon]

I'd guess that would mean even less backpressure, which means less resistance for the air entering the Beckett.