Is this skimmer too big?

[ReefGeezer]

I have 4 tangs ranging from 4 to 6" each. Plus I feed the nems like an ounce or two of food weekly

I'm not experienced with that kind of overstocking and overfeeding. I'll hang up and listen.

 

[jft]

You will have different sides of the story. Personally after running reef tanks for 35 plus years I have HAD better results with Moderate size skimmers versus oversized skimmers. Its also depends on how often you feed the tank, size of fish you keep and how often you do water changes plus use of chemical media. Different Aquarists will have differing opinions. Either way good luck.

 

[92Miata]

When it comes to needlewheel skimmers......there is no such thing as too big.........they just dont mix a ton of air or make really small bubbles........

This is just empirically untrue.


We can measure air draw, and we've been measuring air draw for literally decades.

 

[shakacuz]

In my experience, that skimmer is way oversized.

I used to run a Reef Octo Recirculating 150NWS on my heavily stocked & fed 90 (up to 17 fish, including a 4" Tang, a 4" Hogfish, a 4" Wrasse, and 3X 3-4" Anthias). I had problems getting corals and even Coralline to grow. As the tank became more established, I also had trouble keeping N&P high enough levels. I finally replaced the big skimmer with with a less efficient Bubble Magnus Curve 7. The tank runs well now. I have plenty of Coralline and the corals are growing well. I still have to add a little nitrogen (I use ammonia), but that's because the corals are using it rather than it being exported by the skimmer.

The Curve 7 is probably about right. It is a little finicky though.

what did you have for a sump? i’m currently building up a 75G, and using the BM curve 7, but am concerned about getting it the right water height since the 20G long i have has a water level up to 8inches i believe (fiji cube DIY kit)

 

[ReefGeezer]

what did you have for a sump? i’m currently building up a 75G, and using the BM curve 7, but am concerned about getting it the right water height since the 20G long i have has a water level up to 8inches i believe (fiji cube DIY kit)

I have a Trigger Systems Ruby 36 Sump. I think the skimmer bay is 9.5". I originally had the BM7 on a 1.5" platform, but after it settled in, I have it on the bottom with the control knob set at the lowest setting. It ran fine at 8" also with the control knob in the middle. I just wanted to get rid on f the DIY platform. Like all internal skimmers the Curve is finicky, but maybe more so than others. You'll have to make small changes and wait for it to stabilize each time to get it dialed in. I think it'll run fine even in 7-7.5".

 

[shakacuz]

I have a Trigger Systems Ruby 36 Sump. I think the skimmer bay is 9.5". I originally had the BM7 on a 1.5" platform, but after it settled in, I have it on the bottom with the control knob set at the lowest setting. It ran fine at 8" also with the control knob in the middle. I just wanted to get rid on f the DIY platform. Like all internal skimmers the Curve is finicky, but maybe more so than others. You'll have to make small changes and wait for it to stabilize each time to get it dialed in. I think it'll run fine even in 7-7.5".

thanks. i plan on having a heavy bio load which is why i went with the 7, compared to the 5

 

[theMeat]

Way too big

 

[theMeat]

No such thing as too big of a skimmer. Bigger is better imo.
D

Not with a skimmer.

 

[theMeat]

You will have different sides of the story. Personally after running reef tanks for 35 plus years I have HAD better results with Moderate size skimmers versus oversized skimmers. Its also depends on how often you feed the tank, size of fish you keep and how often you do water changes plus use of chemical media. Different Aquarists will have differing opinions. Either way good luck.

This is my experience as well. Skimmer does best when slightly undersized. Skimmer too big = not enough proteins to collect, and you end up having a finicky skimmer that you have to run at a higher water level and end up collecting watered down skimmate instead of thick dark more concentrated skimmate

 

[monkeyCmonkeyDo]

No. The foam head will.get heavier and heavier with organics and push up the lighter foam head above it. That's just how it works.
D

 

[monkeyCmonkeyDo]

I.could run a 36" tall.lifereef on a 10g display if u had it.set.up right. Np.
D

 

[monkeyCmonkeyDo]

I*

 

[ReefGeezer]

I.could run a 36" tall.lifereef on a 10g display if u had it.set.up right. Np.
D

I think the issue is not whether a big skimmer will work on a small system, but whether it could skim too much. I'll stipulate that skimmers will "Idle" when there are not enough of the affected organics in the water column and perhaps help with dissolved gasses. However, that same characteristic may lead to certain organic levels being too low as they are removed the instant they reach a very low level.
Personally, I'd prefer to size the skimmer so it can run 24/7 and let it be a nutrient pathway, but not the only one.

 

[Rit6942]

This is just empirically untrue.


We can measure air draw, and we've been measuring air draw for literally decades.

My experience its very true. When needlewheels came out the big thing with them was power "efficiency". They didnt draw alot of power. They didnt need big pumps with big ampdraw to power them. Euroreef and Deltec were super popular back 20 years ago. Beckett driven and Venturis were superior but normally needed bigger expensive pressure pumps to drive em drawing big amps. But now you can get a pressure pump that draws less than an amp........so running a skimmer with a Beckett or Mazzei injector is possible without the huge electrical cost monthly.......no different with how ppl run led grow lamps drawing 50-100watts instead of 250-400-600 watt mh bulbs.

My Mazzei skimmer at half the physical size will shut down foam production in my old needlewheel CS-12-2 and pull out dark green sludge in the process. Its fast at removing organic waste. It processes ALOT of air.....its not sucking air thru 1/4 line hobby air line tubing either. Because of that I can heavy feed my corals n fish 5-6 times a day..........and allows me to run my skimmer PART TIME(which imo is better for the overall tank health) keeping particulate matter plentiful in the water column. I havent done a water change in 5 plus years........i have never run any type of filter floss or sock or mechanical filtration either. Heavy PT skimming, DSB, plenty of REAL live rock w all the hitch hikers, multiple refugiums. That it.

 

[theMeat]

My experience its very true. When needlewheels came out the big thing with them was power "efficiency". They didnt draw alot of power. They didnt need big pumps with big ampdraw to power them. Euroreef and Deltec were super popular back 20 years ago. Beckett driven and Venturis were superior but normally needed bigger expensive pressure pumps to drive em drawing big amps. But now you can get a pressure pump that draws less than an amp........so running a skimmer with a Beckett or Mazzei injector is possible without the huge electrical cost monthly.......no different with how ppl run led grow lamps drawing 50-100watts instead of 250-400-600 watt mh bulbs.

My Mazzei skimmer at half the physical size will shut down foam production in my old needlewheel CS-12-2 and pull out dark green sludge in the process. Its fast at removing organic waste. It processes ALOT of air.....its not sucking air thru 1/4 line hobby air line tubing either. Because of that I can heavy feed my corals n fish 5-6 times a day..........and allows me to run my skimmer PART TIME(which imo is better for the overall tank health) keeping particulate matter plentiful in the water column. I havent done a water change in 5 plus years........i have never run any type of filter floss or sock or mechanical filtration either. Heavy PT skimming, DSB, plenty of REAL live rock w all the hitch hikers, multiple refugiums. That it.

Most needle wheel skimmers are venturi. Needle wheel chops up the air into smaller bubbles and creates more surface space for proteins to cling too.

 

[Rit6942]

Most needle wheel skimmers are venturi. Needle wheel chops up the air into smaller bubbles and creates more surface space for proteins to cling too.

Needlewheels are not venturi..........they are aspirating impellar skimmers.

 

[theMeat]

Needlewheels are not venturi..........they are aspirating impellar skimmers.

Venturi has nothing to do with whether the impeller is needle wheel or not. And yes a needle or mesh wheel is can be an “aspirating” impeller. Venturi is how the air is sucked in by reducing input size at pump intake which creates suction that pulls the air in pre pump. Unlike an air driven skimmer where air is injected post pump. Or a downdraft skimmer which uses a jet of water blasted against media which makes bubbles. Or a becket skimmer which can be best described as a hybrid backdraft/venturi.
If your skimmer has a fitting that attaches to the pump input where the air hose is connected, you have a venturi style skimmer, paddle wheel, needle wheel, mesh wheel, whatever.
When it comes to calling a skimmer an aspirated skimmer it’s really just a play on words. Aspirate means breath. The air intake is a venturi by design. The impeller chops up the air.

 

[Rit6942]

Venturi has nothing to do with whether the impeller is needle wheel or not. And yes a needle or mesh wheel is can be an “aspirating” impeller. Venturi is how the air is sucked in by reducing input size at pump intake which creates suction that pulls the air in pre pump. Unlike an air driven skimmer where air is injected post pump. Or a downdraft skimmer which uses a jet of water blasted against media which makes bubbles. Or a becket skimmer which can be best described as a hybrid backdraft/venturi.
If your skimmer has a fitting that attaches to the pump input where the air hose is connected, you have a venturi style skimmer, paddle wheel, needle wheel, mesh wheel, whatever.
When it comes to calling a skimmer an aspirated skimmer it’s really just a play on words. Aspirate means breath. The air intake is a venturi by design. The impeller chops

Venturi has nothing to do with whether the impeller is needle wheel or not. And yes a needle or mesh wheel is can be an “aspirating” impeller. Venturi is how the air is sucked in by reducing input size at pump intake which creates suction that pulls the air in pre pump. Unlike an air driven skimmer where air is injected post pump. Or a downdraft skimmer which uses a jet of water blasted against media which makes bubbles. Or a becket skimmer which can be best described as a hybrid backdraft/venturi.
If your skimmer has a fitting that attaches to the pump input where the air hose is connected, you have a venturi style skimmer, paddle wheel, needle wheel, mesh wheel, whatever.
When it comes to calling a skimmer an aspirated skimmer it’s really just a play on words. Aspirate means breath. The air intake is a venturi by design. The impeller chops up the air.

The "venturi" on the intake side of the pump be it needlewheel or a regular impellar is actually aspiration........water and air are drawn in and mixed. There is no appreciable pressurization. Thats why all thse "needlewheel" skimmers can use cheap little powerhead pumps.

A venturi injector like a Mazzei jet needs a pump that can create high pressure in the mixing chamber which is on the outlet side of the pump reducing absolute pressure.......creating a vacuum........thus drawing air in. The stronger the pressure pump.......the stronger the vacuum.......the more air is drawn in and mixed.

Though i understand what your trying to say and insinuate..........both designs are NOT the same.

 

[theMeat]

The "venturi" on the intake side of the pump be it needlewheel or a regular impellar is actually aspiration........water and air are drawn in and mixed. There is no appreciable pressurization. Thats why all thse "needlewheel" skimmers can use cheap little powerhead pumps.

A venturi injector like a Mazzei jet needs a pump that can create high pressure in the mixing chamber which is on the outlet side of the pump reducing absolute pressure.......creating a vacuum........thus drawing air in. The stronger the pressure pump.......the stronger the vacuum.......the more air is drawn in and mixed.

Though i understand what your trying to say and insinuate..........both designs are NOT the same.

A downdraft skimmer needs a big pump. Or if the venturi was on the output side of pump it would need a bigger pump to achieve the same air draw. The pump on an aspiration skimmer can be smaller because there’s no paddle or scoop. The needles or mesh can pass through the water easily. That’s the way I see it anyway. This doesn’t help op who was asking if the skimmer he picked was too big, which it is. Had heard for decades that if a skimmer was too big it won’t collect much skimmate and will overflow easily. Figured I’d try it anyway, a few times, with a few different skimmers types, and it turns out everyone is right.

 

[Rit6942]

A downdraft skimmer needs a big pump. Or if the venturi was on the output side of pump it would need a bigger pump to achieve the same air draw. The pump on an aspiration skimmer can be smaller because there’s no paddle or scoop. The needles or mesh can pass through the water easily. That’s the way I see it anyway. This doesn’t help op who was asking if the skimmer he picked was too big, which it is. Had heard for decades that if a skimmer was too big it won’t collect much skimmate and will overflow easily. Figured I’d try it anyway, a few times, with a few different skimmers types, and it turns out everyone is right.

A venturi sure does need a "bigger" pump........a pressure pump. Depending on venturi tuning and injector size though will determine air volume pulled in. But the pump is putting full water pressure into the chamber.........with a needlewheel........it draws a mixture of air and water from the pump inlet size..........reducing its thruput. We can go back n forth all day long though, the fact of the matter is ive toyed with modified designed and made countless skimmers over the past 3 decades.........i know what works and how.

As for the OP: That RO 220 sss skimmer is not too big for a 75 gallons, especially a heavy bioload system. Lets throw out the bogus "ratings" all these mfgs give.......they are all honestly overflated to help sell a products thats brutally overpriced to begin with. Instead, lets look at the ACTUAL skimmer itself. The reef Octopus 220 sss is only 24" tall with an 8-9" diameter body. Its not a big skimmer at all. The dc pump w air draw only cranks out a few hundred gallons per hour tops and MAYBE 1500l/h of air. Its smaller than my old retired EuroReef CS12-2 that i had on a 65g Ritteri tank a decade back. That was the smallest skimmer i could get away with on that tank. It had to be cleaned out constantly every few days, and i run my skimmers super dry. Only chunky skimmate and sludge gets into the cup..........not soupy water.......thats not really how a skimmer should be set anyway. Ppl who have "finiky" skimmers normally have issues with sump water levels fluctuating and/or being ABOVE the skimmer output or have the gate valve too restricted(thus watery skimmate) or a dirty or poorly designed skimmer.

But when you get past the balony and advertized "features" of a skimmer you realize its just a big cylinder to mix as much air and water together as it can to remove DOCs. So how big is the chamber and how much air/water mixture can in effectively process?

The reef Octopus is 24" tall with a 9" diameter body...so it will have **** for dwell time....and can only process at most a few hundred gph per hour drawing 1500l/hour at best, so it really cant compensate bubble dwelltime with raw thruput. Its not a big skimmer, not alot of processing power. Not too big for a heavy bioload 75g. If you already got it, it will be ok.......definetly far from "oversized"........if not........imo better choices out there.........