Comparison of Recirc vs. Needlewheel skimmers.

scubaduderon · 03/22/2006, 10:34 PM

I am in a bit of confusion on skimmer theory.

I see needlewheel skimmers with much large capacity numbers (size of tank served) as compared to recirc needlewheels of the same physical size.

When skimmers of the same size are compared with these technologies it seems the straight needlewheels win out. Why is this? It would seem to me that a recirculating model would be able to skim to a lower protien content than a straight needlewheel. Is this correct? Am I missing something?

Thanks,

Scubaduderon

Bebo77 · 03/22/2006, 10:46 PM

thats the theory? why/ where are you saying/ reading different?

h20cooled · 03/22/2006, 10:53 PM

I'm confused on what you are refering to. Most recirc skimmers use needle wheel/ venturi pumps for the recirculation. I'm guessing you are talking about the difference between needle wheel recirc and non-recirculating. Correct?

If so where are you reading this? Take a look at a Deltec skimmer which is a needle wheel recirc skimmer and then compare it to a ER or ASM that is a similar size. The recirc can handle a LOT more volume...

Rich

manderx · 03/22/2006, 11:35 PM

you really can't compare based on manufacturer's numbers. they put whatever number on the box that they think will sell the most skimmers.

hahnmeister · 03/23/2006, 03:27 AM

A single pass skimmer (ER's CS & RS lines, stock ASM, etc.) involve using the mixing pump as the feed for the skimmer as well. If the skimmer is in shallow water, or water lower than the skimmer's water level, this cuts down the pump's capacity pretty fast (NWs are bad w/ back pressure). The water that enters the skimmer then only gets one pass with bubbles before it has to exit the skimmer...often the outlet is only inches below the pump's discharge, so alot of the water simply passes through...and rather fast. Even though those needlewheels arent as fast as a regular pump, they still often pump many hundred gph...that means a shorter exposure time, and this also means microbubbles have an easier time getting out into the system.

Now, for recirculating skimmers like modded ASM, ER's RC series, H&S, deltec, etc...
The water is fed in at the top usually, at a rate that is often a fraction of a single-pass skimmer's rate. That means that the water must pass from the top to the bottom, through a storm of bubbles on the way (no easy ways out the drain), and at a rather slow rate (usually recirc skimmers are fed at 1.5-2x the tank volume per hour). This downdraft path for incoming water greatly increases the exposure of the water to bubbles. This lower rate also means that microbubbles cant escape as easy...the output is just too slow. So then the pump can be made even larger for more bubbles, more capacity, etc. The pump is also drawing water from the same height it is drawing from, and so head-pressure doesnt factor in to the pump's back-pressure. The skimmer is fed with a seperate pump and doesnt make a difference if the water level around the skimmer is 1" or 20"...the pump's throughput no longer is effected...it can always operate at maxmum capacity and minimum back-pressure.

For these reasons, the recirculating skimmers are better performers than single-pass skimmers.

scubaduderon · 03/23/2006, 07:12 AM

Quote:

Originally posted by hahnmeister
A single pass skimmer (ER's CS & RS lines, stock ASM, etc.) involve using the mixing pump as the feed for the skimmer as well. If the skimmer is in shallow water, or water lower than the skimmer's water level, this cuts down the pump's capacity pretty fast (NWs are bad w/ back pressure). The water that enters the skimmer then only gets one pass with bubbles before it has to exit the skimmer...often the outlet is only inches below the pump's discharge, so alot of the water simply passes through...and rather fast. Even though those needlewheels arent as fast as a regular pump, they still often pump many hundred gph...that means a shorter exposure time, and this also means microbubbles have an easier time getting out into the system.

Now, for recirculating skimmers like modded ASM, ER's RC series, H&S, deltec, etc...
The water is fed in at the top usually, at a rate that is often a fraction of a single-pass skimmer's rate. That means that the water must pass from the top to the bottom, through a storm of bubbles on the way (no easy ways out the drain), and at a rather slow rate (usually recirc skimmers are fed at 1.5-2x the tank volume per hour). This downdraft path for incoming water greatly increases the exposure of the water to bubbles. This lower rate also means that microbubbles cant escape as easy...the output is just too slow. So then the pump can be made even larger for more bubbles, more capacity, etc. The pump is also drawing water from the same height it is drawing from, and so head-pressure doesnt factor in to the pump's back-pressure. The skimmer is fed with a seperate pump and doesnt make a difference if the water level around the skimmer is 1" or 20"...the pump's throughput no longer is effected...it can always operate at maxmum capacity and minimum back-pressure.

For these reasons, the recirculating skimmers are better performers than single-pass skimmers.

Better performers, yes, but I often see skimmers with similar internal volumes where the straight needlewheel has a larger rating than the recirc type.

I was theorizing that because the recircs are more thourough they were rated lower due to the fact that they would overflow or pull too much wet skimmate. Being less thorough, a straight needlewheel type would not have this problem and even though it didn't pull as much skimmate it passes so much more water that it gets a higher rating.

Example: if the straight needlewheel was 1/5 as efficient as a recirc but passed 7 times as much water it would pull out more goo and get the higher rating.

I just ordered a recirc and these competing thoughts are running through my mind.

Thank you for your help so far folks but I'm still confused...

Ron

jmcmahon66 · 03/23/2006, 09:38 AM

Hahnmeister puts it very well. The output of my non-modded ASM G-3 is very dependent upon sump water level. This would not be the case if I got the recirc mod on the unit. I still get excellent skimming, but have seen recirc units pull out even more.

scubaduderon · 03/23/2006, 10:08 AM

the recirc skimmer pulls out skimmate even when protien levels are very low in the water. That is what I aml after, the lowest level of contaminants possible.

Dwell time should be maximised and the interface between the bubbles and water should be as calm as possible, so as not to disturb the developing high protien area rising in the skimmer.

Ron

Amphiprion · 03/23/2006, 11:34 AM

You got it.

Fliger · 03/23/2006, 11:38 AM

You got it right Ron. I like recircs because you can control the water height independant of the air intake and vice versa. Its much easier to adjust for wet vs dry skimmate. Since the same tank can go from high to low protein/nutrient levels quickly, its nice to be able to adjust for it. The last several skimmers I've run were all recirc (ER, H&S, BK, Deltec) and now I'm using a non-recirc on a holding tank and I hate it. Maybe if I wasn't so used to externals, I'd like it more. Another benefit is that the pump is not submerged so it adds less heat to the tank. Mostly though - I love gravity feedind externals RC from the the overflow. The overflow water will always be the dirtiest, and you are certain that the skimmer body is filled with 100% surface water - not just recirculating the same sump water.

scubaduderon · 03/23/2006, 11:48 AM

Does the water level in the sump affect the performance of a recirc skimmer as much as a straight needlewheel? In order for me to fit the skimmer I wanted into the sump I had to change it to a rubbermaid 15 gallon tub. The water level is about 4 inches deep. I realise I could put another higher container inside the tub but I would like to avoid that if possible.

Also how do I plumb the overflow to the skimmer? Currently I have a 1.25 inch inside diameter hose running from an overflow to the sump. I run about 400 to 500 gallons an hour through the sump.

Thank you,

Ron

Fliger · 03/23/2006, 11:53 AM

Well there is another reason why a recirculating would be better for you. ;-) If you run a recirculating skimmer in-sump, the water level will not affect your skimming - so long as you feed it with your overflow (which is always preferred). If you fed it with a powerhead, it would - if your water level fluctuated in the sump.

You do not have to run all 400-500 thru the skimmer though - a simple ball valve and a "T" should do the trick.

tigerarmy40 · 03/23/2006, 12:07 PM

I am getting a new asm g-3 for 219.99+tax wich is a great deal, there is a lfs that quoted me that about 6 months ago and is willing to honor it!!! however I am wondering if it is really dificult to make into a recirc model, Im not the best DIY'er and would hate to damage my investment....anyone here know what exactly Ill need? sorry for the hijack but it kinda falls under this topic. I have a 150g 60x24x24 and Im planning on doing a sps tank but dont know if this will be enough skimmer for what I want to run...modded or not?

Fliger · 03/23/2006, 12:16 PM

I would check that monstrous ASM Club thread. There are lots of mods in there for you. I love your avatar. SHO NUFF. My favorite terrible movie, I think I know every line. ;-)

scubaduderon · 03/23/2006, 12:22 PM

I'm a little curious how it will work though.

Currently the overflow has no restriction on it therefore no back pressure. If I put a restriction on it to feed the skimmer won't this affect the rate at which the sump fills? I can picture the water rising up through the tube running to the tee. It will reach a height at which forces are equal. I don't know what this will do to the overflow. There may be a tricky interplay between everything. If I restrict the flow out of the overflow too much it could potentially flood my room.....

How have you handled this? Am I thinking too hard here?

Ron

tigerarmy40 · 03/23/2006, 01:44 PM

I will be dealing with this soon and I have always thought that one should have the water coming from the overflow run through a sponge or filter sock before the skimmer....wouldnt that make more sense? I would think that skimmer cleaning might be neede more often if not!?!? I guess the skimmer can remove particulate matter but for the heavier stuff I could see it laying on the bottom of the skimmer....

jmcmahon66 · 03/23/2006, 02:22 PM

Take a look at asmskimmer.com for info on mods. It is relatively straight forward but does require drilling into your new G3. Good Luck.

hahnmeister · 03/23/2006, 02:38 PM

scubaduderon, you said,
"Better performers, yes, but I often see skimmers with similar internal volumes where the straight needlewheel has a larger rating than the recirc type."

Show me. I have never seen this myself, as usually with the two skimmers with the same capacity, one recirc, one single-pass, the recirc has a much smaller body with the same size pump (or larger).

scubaduderon · 03/23/2006, 03:10 PM

Quote:

Originally posted by hahnmeister
scubaduderon, you said,
"Better performers, yes, but I often see skimmers with similar internal volumes where the straight needlewheel has a larger rating than the recirc type."

Show me. I have never seen this myself, as usually with the two skimmers with the same capacity, one recirc, one single-pass, the recirc has a much smaller body with the same size pump (or larger).

Try these 2:

Pacific coast Imports PS-2000 Protein Skimmer with needle wheel impeller 5.85" Diameter 21.45" High up to 300 gallon aquariums.

RPS-2000 Recirculating Protein Skimmer 5.85" Diameter 26.52" Tall with needle wheel impeller for aquariums up to 185 gallons
Footprint 7" x 15"

Similar internal volumes but the recirc has a much smaller stated capacity. Why?

Ron

tm613 · 03/23/2006, 03:25 PM

Also check H&S they rate in and out exactly the same:

In sump 150-F2001 Rated for 225 gallons
Pump: AquaBee 2001/38w
Diameter: 6"
Height: 20"
Footprint: 7"x14"

External A150-F2001 rated for 225 gallons
Pump: AquaBee 2001/38w
Diameter: 6"
Height: 26"
Footprint: 7"x16"
Actually 6" taller but I believe this is done becasue the pump inlet is now higher on the body

ErikS · 03/23/2006, 03:30 PM

Quote:

Similar internal volumes but the recirc has a much smaller stated capacity. Why?

Because some companies, such as Pacific Coast in this case decieve....they WAY overstate the capacity of their skimmers. Why do they do this? Simple, there's no standard of measurement so who's to say it's not. There is NO way that skimmer can handle 300g.

Check companies like Deltec, H&S, and ER - they give a much more accurate rating.

scubaduderon · 03/23/2006, 06:23 PM

Quote:

Originally posted by ErikS
Because some companies, such as Pacific Coast in this case decieve....they WAY overstate the capacity of their skimmers. Why do they do this? Simple, there's no standard of measurement so who's to say it's not. There is NO way that skimmer can handle 300g.

Check companies like Deltec, H&S, and ER - they give a much more accurate rating.

Don't similarly sized skimmers using similar technology perform similarly?

If so then is the recirc I'm considering, the RPS-2000 which is rated at 185 gallons may be closer to the mark ratings wise?

It is a recirc needlewheel with a 5.85 inch diameter and 26.52 inches tall. Wouldn't this be comparable to a Deltec APF600, at 5 inches in diameter and a height of 23.5 inches? The Deltec is rated at 270 gallons and is physically smaller than the Pacific Coast model.

Perhaps the Pacific Coast skimmers have their numbers switched around? Maybe the needlewheel recirc should have the higher rating. This would explain my confusion.

Thank you,
Ron

UCanDoIt · 03/24/2006, 01:24 AM

i personally wouldn't trust Pacific's #s as they seem optimistic. same with ASM skimmers. if there's a club forum for a particular line of skimmers, you'll get better #s there.

you asked about how to T off and not worry about flooding, here's an example. Ball valve controls flow to the skimmer, while any excess goes directly back into the sump through the opposite direction of the T. this diagram created by my aquarium technician who maintains my tank sets up all his clients this way as it reduces surging to the skimmer to a minimum. surging cause uneven water level inside the skimmer.

scubaduderon · 03/24/2006, 07:11 AM

Quote:

Originally posted by UCanDoIt
i personally wouldn't trust Pacific's #s as they seem optimistic. same with ASM skimmers. if there's a club forum for a particular line of skimmers, you'll get better #s there.

you asked about how to T off and not worry about flooding, here's an example. Ball valve controls flow to the skimmer, while any excess goes directly back into the sump through the opposite direction of the T. this diagram created by my aquarium technician who maintains my tank sets up all his clients this way as it reduces surging to the skimmer to a minimum. surging cause uneven water level inside the skimmer.

Perfect. The water will back up and naturally divert itself to the no back pressure side. Thank you.

As far as the numbers go I understand your sentiments. Perhaps after a while people will get to know these units and better figures will come out. The unit I picked for my tank is rated at 4 times the capacity of my tank. Hopefully it will suffice.

You'll be seeing a thread by yours truely telling of my experiences with it.

Thanks again,

Ron

UCanDoIt · 03/24/2006, 10:36 AM

What really makes a skimmer is the needlewheel pump. My experience with the German pumps, AquaBee & Eheim, is they out perform any China made pumps made to date. There's just no comparison as the efficient German pumps can take a small cylinder skimmer and out perform even the larger USA cylinder skimmers. I have a AP600 and need to empty and clean the collection cup every 2-3 days on a 75g tank, then I really like to overskim and skim wet. I know that Deltecs are expensive, but IMO they are accurately rated.

03/22/2006, 10:34 PM	#1
scubaduderon Registered Member Join Date: Nov 2003 Location: Chicagoland (Western Burbs) Posts: 188	Comparison of Recirc vs. Needlewheel skimmers. I am in a bit of confusion on skimmer theory. I see needlewheel skimmers with much large capacity numbers (size of tank served) as compared to recirc needlewheels of the same physical size. When skimmers of the same size are compared with these technologies it seems the straight needlewheels win out. Why is this? It would seem to me that a recirculating model would be able to skim to a lower protien content than a straight needlewheel. Is this correct? Am I missing something? Thanks, Scubaduderon

03/22/2006, 10:46 PM	#2
Bebo77 Premium Nonpaying Member Join Date: Jul 2005 Location: Lost Posts: 14,377	thats the theory? why/ where are you saying/ reading different? __________________ Gabriel Current Tank Info: 300 Gal Envision Tank(98Lx30Wx26T) 120 Gal SoCalCreations Sump, Deltec TC2560, 2 LumenarcsMini 1 Reg on a light mover W Radiums 250& 400, Gallaxy ballasts, Red Dragon 10m3 return W/ 2 WavySeas, 2 6155 Tunze streams

03/23/2006, 09:38 AM	#7
jmcmahon66 Registered Member Join Date: Oct 2004 Location: Chicago. Illinois Posts: 439	Hahnmeister puts it very well. The output of my non-modded ASM G-3 is very dependent upon sump water level. This would not be the case if I got the recirc mod on the unit. I still get excellent skimming, but have seen recirc units pull out even more. __________________ I ain't no hula-hoop-eyed, chicken-necked lookin' jive turkey. Current Tank Info: 150g RR Oceanic, 750W 20K MH with 300W 14K MH, Deltec Turbo 1060 skimmer, Tunzes with controller, all types of corals-but mostly SPS and Acans

03/23/2006, 10:08 AM	#8
scubaduderon Registered Member Join Date: Nov 2003 Location: Chicagoland (Western Burbs) Posts: 188	So then.... the recirc skimmer pulls out skimmate even when protien levels are very low in the water. That is what I aml after, the lowest level of contaminants possible. Dwell time should be maximised and the interface between the bubbles and water should be as calm as possible, so as not to disturb the developing high protien area rising in the skimmer. Ron

03/23/2006, 11:34 AM	#9
Amphiprion Premium Member Join Date: Jul 2005 Location: Mobile, AL Posts: 6,611	You got it. __________________ You've done it now, haven't you? Current Tank Info: 40g breeder patch reef w/ seagrass; 2-250w XM 10K; Vortech MP40wES & MP10wES; BM Curve 7 skimmer; carbon & occasional GFO

03/22/2006, 10:53 PM	#3
h20cooled Premium Member Join Date: Dec 2003 Location: Milwaukie, OR Posts: 1,016	I'm confused on what you are refering to. Most recirc skimmers use needle wheel/ venturi pumps for the recirculation. I'm guessing you are talking about the difference between needle wheel recirc and non-recirculating. Correct? If so where are you reading this? Take a look at a Deltec skimmer which is a needle wheel recirc skimmer and then compare it to a ER or ASM that is a similar size. The recirc can handle a LOT more volume... Rich

03/22/2006, 11:35 PM	#4
manderx Registered Member Join Date: Mar 2002 Location: Christiansburg, VA Posts: 4,893	you really can't compare based on manufacturer's numbers. they put whatever number on the box that they think will sell the most skimmers.

03/23/2006, 03:27 AM	#5
hahnmeister Moved On Join Date: Sep 2005 Location: Brew City, WI Posts: 10,156	A single pass skimmer (ER's CS & RS lines, stock ASM, etc.) involve using the mixing pump as the feed for the skimmer as well. If the skimmer is in shallow water, or water lower than the skimmer's water level, this cuts down the pump's capacity pretty fast (NWs are bad w/ back pressure). The water that enters the skimmer then only gets one pass with bubbles before it has to exit the skimmer...often the outlet is only inches below the pump's discharge, so alot of the water simply passes through...and rather fast. Even though those needlewheels arent as fast as a regular pump, they still often pump many hundred gph...that means a shorter exposure time, and this also means microbubbles have an easier time getting out into the system. Now, for recirculating skimmers like modded ASM, ER's RC series, H&S, deltec, etc... The water is fed in at the top usually, at a rate that is often a fraction of a single-pass skimmer's rate. That means that the water must pass from the top to the bottom, through a storm of bubbles on the way (no easy ways out the drain), and at a rather slow rate (usually recirc skimmers are fed at 1.5-2x the tank volume per hour). This downdraft path for incoming water greatly increases the exposure of the water to bubbles. This lower rate also means that microbubbles cant escape as easy...the output is just too slow. So then the pump can be made even larger for more bubbles, more capacity, etc. The pump is also drawing water from the same height it is drawing from, and so head-pressure doesnt factor in to the pump's back-pressure. The skimmer is fed with a seperate pump and doesnt make a difference if the water level around the skimmer is 1" or 20"...the pump's throughput no longer is effected...it can always operate at maxmum capacity and minimum back-pressure. For these reasons, the recirculating skimmers are better performers than single-pass skimmers.

03/23/2006, 11:38 AM	#10
Fliger Registered Member Join Date: Feb 2003 Location: Chandler, AZ Posts: 8,642	You got it right Ron. I like recircs because you can control the water height independant of the air intake and vice versa. Its much easier to adjust for wet vs dry skimmate. Since the same tank can go from high to low protein/nutrient levels quickly, its nice to be able to adjust for it. The last several skimmers I've run were all recirc (ER, H&S, BK, Deltec) and now I'm using a non-recirc on a holding tank and I hate it. Maybe if I wasn't so used to externals, I'd like it more. Another benefit is that the pump is not submerged so it adds less heat to the tank. Mostly though - I love gravity feedind externals RC from the the overflow. The overflow water will always be the dirtiest, and you are certain that the skimmer body is filled with 100% surface water - not just recirculating the same sump water. __________________ Growing old is mandatory, growing up is optional. Closed minds should come with closed mouths. When life hands you lemons, add vodka! Current Tank Info: Current: 210G Elos System, 2x400W + 6x54W Photon w/Aquaconnects, H&S skimmer, Deltec FR509/ROWAphos+Elos Carbon, 6101's and 6201's, Ocean GEOtronic 900 Chiller/Heater, Biotopus II Controller w/SMS. Elos System 70.

03/23/2006, 11:48 AM	#11
scubaduderon Registered Member Join Date: Nov 2003 Location: Chicagoland (Western Burbs) Posts: 188	I'm planning my skimmer in sump. Does the water level in the sump affect the performance of a recirc skimmer as much as a straight needlewheel? In order for me to fit the skimmer I wanted into the sump I had to change it to a rubbermaid 15 gallon tub. The water level is about 4 inches deep. I realise I could put another higher container inside the tub but I would like to avoid that if possible. Also how do I plumb the overflow to the skimmer? Currently I have a 1.25 inch inside diameter hose running from an overflow to the sump. I run about 400 to 500 gallons an hour through the sump. Thank you, Ron

03/23/2006, 11:53 AM	#12
Fliger Registered Member Join Date: Feb 2003 Location: Chandler, AZ Posts: 8,642	Well there is another reason why a recirculating would be better for you. ;-) If you run a recirculating skimmer in-sump, the water level will not affect your skimming - so long as you feed it with your overflow (which is always preferred). If you fed it with a powerhead, it would - if your water level fluctuated in the sump. You do not have to run all 400-500 thru the skimmer though - a simple ball valve and a "T" should do the trick. __________________ Growing old is mandatory, growing up is optional. Closed minds should come with closed mouths. When life hands you lemons, add vodka! Current Tank Info: Current: 210G Elos System, 2x400W + 6x54W Photon w/Aquaconnects, H&S skimmer, Deltec FR509/ROWAphos+Elos Carbon, 6101's and 6201's, Ocean GEOtronic 900 Chiller/Heater, Biotopus II Controller w/SMS. Elos System 70.

03/23/2006, 12:07 PM	#13
tigerarmy40 Registered Member Join Date: Dec 2004 Location: central ca Posts: 1,831	I am getting a new asm g-3 for 219.99+tax wich is a great deal, there is a lfs that quoted me that about 6 months ago and is willing to honor it!!! however I am wondering if it is really dificult to make into a recirc model, Im not the best DIY'er and would hate to damage my investment....anyone here know what exactly Ill need? sorry for the hijack but it kinda falls under this topic. I have a 150g 60x24x24 and Im planning on doing a sps tank but dont know if this will be enough skimmer for what I want to run...modded or not? __________________ The power of moonlight Current Tank Info: 90g rimless tank in the makes and a 15g nano

03/23/2006, 12:16 PM	#14
Fliger Registered Member Join Date: Feb 2003 Location: Chandler, AZ Posts: 8,642	I would check that monstrous ASM Club thread. There are lots of mods in there for you. I love your avatar. SHO NUFF. My favorite terrible movie, I think I know every line. ;-) __________________ Growing old is mandatory, growing up is optional. Closed minds should come with closed mouths. When life hands you lemons, add vodka! Current Tank Info: Current: 210G Elos System, 2x400W + 6x54W Photon w/Aquaconnects, H&S skimmer, Deltec FR509/ROWAphos+Elos Carbon, 6101's and 6201's, Ocean GEOtronic 900 Chiller/Heater, Biotopus II Controller w/SMS. Elos System 70.

03/23/2006, 12:22 PM	#15
scubaduderon Registered Member Join Date: Nov 2003 Location: Chicagoland (Western Burbs) Posts: 188	I'll give it a try, but... I'm a little curious how it will work though. Currently the overflow has no restriction on it therefore no back pressure. If I put a restriction on it to feed the skimmer won't this affect the rate at which the sump fills? I can picture the water rising up through the tube running to the tee. It will reach a height at which forces are equal. I don't know what this will do to the overflow. There may be a tricky interplay between everything. If I restrict the flow out of the overflow too much it could potentially flood my room..... How have you handled this? Am I thinking too hard here? Ron

03/23/2006, 01:44 PM	#16
tigerarmy40 Registered Member Join Date: Dec 2004 Location: central ca Posts: 1,831	I will be dealing with this soon and I have always thought that one should have the water coming from the overflow run through a sponge or filter sock before the skimmer....wouldnt that make more sense? I would think that skimmer cleaning might be neede more often if not!?!? I guess the skimmer can remove particulate matter but for the heavier stuff I could see it laying on the bottom of the skimmer.... __________________ The power of moonlight Current Tank Info: 90g rimless tank in the makes and a 15g nano

03/23/2006, 02:22 PM	#17
jmcmahon66 Registered Member Join Date: Oct 2004 Location: Chicago. Illinois Posts: 439	Take a look at asmskimmer.com for info on mods. It is relatively straight forward but does require drilling into your new G3. Good Luck. __________________ I ain't no hula-hoop-eyed, chicken-necked lookin' jive turkey. Current Tank Info: 150g RR Oceanic, 750W 20K MH with 300W 14K MH, Deltec Turbo 1060 skimmer, Tunzes with controller, all types of corals-but mostly SPS and Acans

03/23/2006, 02:38 PM	#18
hahnmeister Moved On Join Date: Sep 2005 Location: Brew City, WI Posts: 10,156	scubaduderon, you said, "Better performers, yes, but I often see skimmers with similar internal volumes where the straight needlewheel has a larger rating than the recirc type." Show me. I have never seen this myself, as usually with the two skimmers with the same capacity, one recirc, one single-pass, the recirc has a much smaller body with the same size pump (or larger).

03/23/2006, 03:25 PM	#20
tm613 Registered Member Join Date: Mar 2003 Location: Fairless Hills,PA Posts: 407	Also check H&S they rate in and out exactly the same: In sump 150-F2001 Rated for 225 gallons Pump: AquaBee 2001/38w Diameter: 6" Height: 20" Footprint: 7"x14" External A150-F2001 rated for 225 gallons Pump: AquaBee 2001/38w Diameter: 6" Height: 26" Footprint: 7"x16" Actually 6" taller but I believe this is done becasue the pump inlet is now higher on the body

03/24/2006, 01:24 AM	#23
UCanDoIt Moved On Join Date: Mar 2006 Location: Bay Area CA Posts: 1,684	i personally wouldn't trust Pacific's #s as they seem optimistic. same with ASM skimmers. if there's a club forum for a particular line of skimmers, you'll get better #s there. you asked about how to T off and not worry about flooding, here's an example. Ball valve controls flow to the skimmer, while any excess goes directly back into the sump through the opposite direction of the T. this diagram created by my aquarium technician who maintains my tank sets up all his clients this way as it reduces surging to the skimmer to a minimum. surging cause uneven water level inside the skimmer.

03/24/2006, 10:36 AM	#25
UCanDoIt Moved On Join Date: Mar 2006 Location: Bay Area CA Posts: 1,684	What really makes a skimmer is the needlewheel pump. My experience with the German pumps, AquaBee & Eheim, is they out perform any China made pumps made to date. There's just no comparison as the efficient German pumps can take a small cylinder skimmer and out perform even the larger USA cylinder skimmers. I have a AP600 and need to empty and clean the collection cup every 2-3 days on a 75g tank, then I really like to overskim and skim wet. I know that Deltecs are expensive, but IMO they are accurately rated.