Skimmers: Countercurrent VS. Venturi

wsboyette · 08/18/2008, 09:41 AM

I am puzzled by something that I read saying that the countercurrent type skimmer will remove a greater variety of dissolved organics, toxins, etc. than a venturi type skimmer. After having been out of operation with my tanks shut down for some years, I was surprised to see so many venturi skimmers and apparently no countercurrent types when I browsed the vendors' websites. It would seem to me that if the bubble size and air/water contact time are equal between the two types, then there would be no difference to make one outperform the other. Has anyone else heard of this claim, and is it true ?

ReefWreak · 08/18/2008, 10:06 AM

I have not heard of that claim, however I can say that noone will really have answer anymore, as most people do not use either of those technologies anymore. They've kind of gone the way of the undergravel filter in the reefkeeping hobby. Sure, they work, and some people still use those skimmers to a large degree, but I would venture to say that most people have moved to either Needlewheel (which still uses a venturi, but in a different fashion) or injection through a beckett valve or downdraft pipe. I used to run an old LifeReef VS2-24, and that was a straight up venturi, so I know what you're talking about with venturi skimmers, but times and technology have changed.

Aj Flip · 08/18/2008, 10:54 AM

id say recirculating with venturi and needle wheel with mesh mod is pwnage

wsboyette · 08/18/2008, 12:06 PM

Thanks guys,

I was out of it for so long that I had gotten behind on the technology. I had seen the needlewheel but was of course puzzled by it. I still have my old Sea-Thru countercurrent unit, which had performed well long ago but took quite a bit of tweaking. It is also an external hang-on type, which requires unsightly powerhead and plumbing to run it. I am going with a Berlin setup this time using a skimmer in the sump tank.

stanlalee · 08/18/2008, 12:36 PM

I dont see "so many" REAL venturi skimmers out there. there are the handful of becketts, Bermuda, Elos and probably a few other REAL venturi nozzle designs but for the most part the market is flooded with air aspirating skimmers (needle wheel, pin wheel, mesh wheel, regular paddle wheel). Counter currents must be rare or out of favor because I dont know of ANY. I hear the term thrown around alot just like I hear the term venturi thrown around alot on skimmers that arent venturi skimmers in the least.

tangtang clown · 08/18/2008, 09:38 PM

Needle Wheels, Mesh Wheels, and airlines on the intake side of the pumps seem to be doing the trick nowadays. I would say undergravel filters are gone and people rely more on natural filtration; live rock, reugium, etc. Not so much mechanical filtration any more.
"2 Sense"

J-Burns · 08/19/2008, 04:21 PM

I think you can have a countercurrent skimmer with a venturi, neddle wheel or what ever. It is just the way the manufactuer makes the internal baffles.

tangtang clown · 08/20/2008, 06:27 AM

Does anyone have pics of these different types of skimmies?

wsboyette · 10/12/2011, 07:19 AM

The efficiency of a skimmer is a direct function of the contact time between the air bubbles and the water. Whether it is a simple venturi, needlewheel, or the old contercurrent type is irrelevant. The one that maximizes that contact time the most will be the most efficient.

J-Burns · 10/12/2011, 07:02 PM

This thread is a little old.

08/18/2008, 09:41 AM	#1
wsboyette Registered Member Join Date: Aug 2008 Location: N.E.N.C. Posts: 140	Skimmers: Countercurrent VS. Venturi I am puzzled by something that I read saying that the countercurrent type skimmer will remove a greater variety of dissolved organics, toxins, etc. than a venturi type skimmer. After having been out of operation with my tanks shut down for some years, I was surprised to see so many venturi skimmers and apparently no countercurrent types when I browsed the vendors' websites. It would seem to me that if the bubble size and air/water contact time are equal between the two types, then there would be no difference to make one outperform the other. Has anyone else heard of this claim, and is it true ?

08/18/2008, 12:06 PM	#4
wsboyette Registered Member Join Date: Aug 2008 Location: N.E.N.C. Posts: 140	Thanks guys, I was out of it for so long that I had gotten behind on the technology. I had seen the needlewheel but was of course puzzled by it. I still have my old Sea-Thru countercurrent unit, which had performed well long ago but took quite a bit of tweaking. It is also an external hang-on type, which requires unsightly powerhead and plumbing to run it. I am going with a Berlin setup this time using a skimmer in the sump tank. Last edited by wsboyette; 08/18/2008 at 12:19 PM.

08/18/2008, 09:38 PM	#6
tangtang clown Registered Member Join Date: Mar 2008 Location: The DUB, NC Posts: 2,711	Needle Wheels, Mesh Wheels, and airlines on the intake side of the pumps seem to be doing the trick nowadays. I would say undergravel filters are gone and people rely more on natural filtration; live rock, reugium, etc. Not so much mechanical filtration any more. "2 Sense" __________________ Mind over chatter.

08/20/2008, 06:27 AM	#8
tangtang clown Registered Member Join Date: Mar 2008 Location: The DUB, NC Posts: 2,711	Does anyone have pics of these different types of skimmies? __________________ Mind over chatter.

10/12/2011, 07:19 AM	#9
wsboyette Registered Member Join Date: Aug 2008 Location: N.E.N.C. Posts: 140	The efficiency of a skimmer is a direct function of the contact time between the air bubbles and the water. Whether it is a simple venturi, needlewheel, or the old contercurrent type is irrelevant. The one that maximizes that contact time the most will be the most efficient. __________________ Oh..... Fishy Fishy Fishy FISH ! Current Tank Info: 60 Gallon Fish-Only With Dry Rock, Filtration: Aquamaxx HOB Filter/Skimmer & Aqua-Tech 30-60 300 GPH HOB Motor Filter, Livestock: Coral Beauty and Maroon Clown

08/18/2008, 10:06 AM	#2
ReefWreak Registered Member Join Date: Sep 2005 Location: Astoria, NYC Posts: 10,159	I have not heard of that claim, however I can say that noone will really have answer anymore, as most people do not use either of those technologies anymore. They've kind of gone the way of the undergravel filter in the reefkeeping hobby. Sure, they work, and some people still use those skimmers to a large degree, but I would venture to say that most people have moved to either Needlewheel (which still uses a venturi, but in a different fashion) or injection through a beckett valve or downdraft pipe. I used to run an old LifeReef VS2-24, and that was a straight up venturi, so I know what you're talking about with venturi skimmers, but times and technology have changed.

08/18/2008, 10:54 AM	#3
Aj Flip Registered Member Join Date: Dec 2007 Posts: 802	id say recirculating with venturi and needle wheel with mesh mod is pwnage

08/18/2008, 12:36 PM	#5
stanlalee Registered Member Join Date: Aug 2006 Location: hampton roads, va Posts: 1,799	I dont see "so many" REAL venturi skimmers out there. there are the handful of becketts, Bermuda, Elos and probably a few other REAL venturi nozzle designs but for the most part the market is flooded with air aspirating skimmers (needle wheel, pin wheel, mesh wheel, regular paddle wheel). Counter currents must be rare or out of favor because I dont know of ANY. I hear the term thrown around alot just like I hear the term venturi thrown around alot on skimmers that arent venturi skimmers in the least.

08/19/2008, 04:21 PM	#7
J-Burns Registered Member Join Date: Jan 2002 Location: Charleston, WV Posts: 235	I think you can have a countercurrent skimmer with a venturi, neddle wheel or what ever. It is just the way the manufactuer makes the internal baffles.

10/12/2011, 07:02 PM	#10
J-Burns Registered Member Join Date: Jan 2002 Location: Charleston, WV Posts: 235	This thread is a little old.