quietest return pump

[tlo]

Hi ,I am looking for recommendations for the quietest return pump that I can possibly get. I am looking for an external 2000-2700 gph. I have a reeflo barracuda right now and I can hear it from the next room. Right now I am willing to pay anything, as long as it is SILENT.

[Red Coral Aquariums]

dart super gold

[tlo]

I am feeling a little fed up with sequence pumps. This is my 3rd one(one was replaced on warrenty) Is the gold series quite a bit quieter?

[lastlight]

my dart gold is pretty quiet. In the next room I only notice it if I'm listening for it.

[mark]

compared to Barracuda even a regular Dart is near silent (have both).

[golf nut]

2700 sounds like a lot of water for a sump return, why so much?

[Parker]

I have three darts on my tank and they each put out various levels of noise, but for the most part they are pretty quiet.

[sphelps]

Red Dragon 10 m3 fits your requirements, not sure about your budget though. I'm running a 6.5 and I can't even tell it's on unless I place my hand on it. It runs very cool and has very little vibration. The new gens now have anti lime bypasses and titanium shafts so be sure not to get old stock if you go for it.

I haven't seen the gold dart in action yet but every other reeflo pump was noisy in my books.

[Parker]

2700 sounds like a lot of water for a sump return, why so much?


It would depend on the size of your tank and sump. A Dart on my tank works out to about 10x turnover, my 75 gallon sump handles the flow just fine. No micro bubble issues etc.

That much flow through a smaller sump and tank and your more then likely going to run into issues.

[Gizmo]

I run 3 darts and they are whisper quiet.

[The Codfather]

I agree with Kevin Super Dart Gold, Mine is very quiet, the DC fans above my aquarium are louder.

[sphelps]

It appears that some suppliers are listing the Dart Gold as discontinued??

The problem with Reeflo pumps is that they are notorious for break downs. I used two darts on my previous tank, one on the closed loop and the other on the return. The closed loop pump was fine the entire time I owned it, other than being a little noisy and requiring significant maintenance I never had a problem with it. However the return pump was replaced 3 times due to the seal leaking and causing the bearing to fail. The first pump only lasted a couple months from new. A quick search will show I'm not the only one with such problems, many owners have gone through this. In fact it was such a common issue Reeflo now requires you to handle all warranty issues through the manufacturer because all there distributors got sick of dealing with them.

The other problem I see with the Gold series is the price, over $400 for the Dart. Sorry but I can't see it being worth that much. A RD doesn't cost that much more in comparison and will actually last. There are no seals to fail, uses less power, better bearings, better shaft and impeller, much quieter and it's got the reputation to back it all up. I would honestly bet you'll need at least 2 darts to match the reliability and lifespan of an RD, that easily puts them at the same price. Remember you'll need a back up pump if you use a reeflo :wink:

[lastlight]

If you compare the number of Sequence customers to the number of Red Dragon owners though and then take into the account that there are plenty of people who've had issues with the RD pumps then I'm not so sold on the idea of paying a lot more for a RD that has the same flow.

Just take a peek at the Proline forum on RC. I've had issues with my RD and with my Dart running I can def hear it when I fire it up. This was after I swapped motor blocks, impellers you name it. Ive only run it in FW and have heard they will run differently in it but I'm not 100% sold on the pump quality myself. There was even a large recall recently. It was the RDII line but still...

Bad news if the Gold series is discontinued. I'm hoping seals etc will still be available!

If I did it over again I'd likely just buy a pair of large Eheims. Definitely quieter than the Dart (even the Baldor Gold) and maybe quieter than the RD pump I have.

[Canadian]

I have three darts on my tank and they each put out various levels of noise, but for the most part they are pretty quiet.

Obviously there are different schools of though on this but I don't see the point in running a return pump at a rate greater than what your skimmer can accommodate. It would be a complete waste of hydro. I'd run the smallest return pump you can to meet your head loss needs to keep up with your skimmer and only use propeller pumps for flow in the display and even one in the sump to keep detritus from collecting.

[sphelps]

Obviously there are different schools of though on this but I don't see the point in running a return pump at a rate greater than what your skimmer can accommodate. It would be a complete waste of hydro. I'd run the smallest return pump you can to meet your head loss needs to keep up with your skimmer and only use propeller pumps for flow in the display and even one in the sump to keep detritus from collecting.
A good point but I see more to a sump than a skimmer. A higher return increases tank flow and reduces the demand for supplemental in tank flow, a big plus in my books. Also more flow increases surface tension and reduces scum build up in the display, it will also keep things suspended longer and filter more out of the display sending it to the sump quicker. Sumps can also hold mechanical filtration like socks and floss and chemical like carbon. These can benefit from higher flow. Finally things like heaters and pumps will work better with an increased convective heat transfer effect.

You don't have to run high flow but there are certainly benefits to it.

[sphelps]

If you compare the number of Sequence customers to the number of Red Dragon owners though and then take into the account that there are plenty of people who've had issues with the RD pumps then I'm not so sold on the idea of paying a lot more for a RD that has the same flow.

Just take a peek at the Proline forum on RC. I've had issues with my RD and with my Dart running I can def hear it when I fire it up. This was after I swapped motor blocks, impellers you name it. Ive only run it in FW and have heard they will run differently in it but I'm not 100% sold on the pump quality myself. There was even a large recall recently. It was the RDII line but still...

The RDIIs have been recalled, it was brand new to the NA market and obviously there was an issue adapting the pump to fit NA requirements. It's unfortunate but being innovative enough to provide the first DC controllable return pump to NA from another country is bound to have some drawbacks, proper testing is virtually impossible. Other than that a quick glance at the forum shows no indication of a problem with regular RD pumps. Sometimes you get faulty products but any distributor of such a pump should stand behind it. If there is an actual problem with the pump you should get a full replacement.

Also I wasn't aware you were running an RD return pump, of course a RD skimmer pump will make some noise because of the air but it is common knowledge that it's still quieter than most alternatives.

[globaldesigns]

I use a Ocean Runner 6500 by AquaMedic. It is very powerful and runs my 300G setup and is whisper quite. I don't hear a thing, can't say that for my skimmers though, but oh well.

[Parker]

Obviously there are different schools of though on this but I don't see the point in running a return pump at a rate greater than what your skimmer can accommodate. It would be a complete waste of hydro. I'd run the smallest return pump you can to meet your head loss needs to keep up with your skimmer and only use propeller pumps for flow in the display and even one in the sump to keep detritus from collecting.

A good point but I see more to a sump than a skimmer. A higher return increases tank flow and reduces the demand for supplemental in tank flow, a big plus in my books. Also more flow increases surface tension and reduces scum build up in the display, it will also keep things suspended longer and filter more out of the display sending it to the sump quicker. Sumps can also hold mechanical filtration like socks and floss and chemical like carbon. These can benefit from higher flow. Finally things like heaters and pumps will work better with an increased convective heat transfer effect.

You don't have to run high flow but there are certainly benefits to it.


My number one reason for running a large return pump is I have enough flow from one pump to drive my entire mechanical system sans skimmer from one pump. My dart supplies my carbon and phosphate reactors, calc reactor, UV filter, fuge and tank return. Also, if your running your skimmer passively in your sump ( your return isn't plumbed directly into the skimmer ) your not skimming the entire contents of water flowing through that chamber, I don't think how fast or slow the water is flowing past the skimmer makes much of a difference. The skimmer still processes the same amount of water.

My second reason for running two additional darts is astetics. If I can avoid seeing mechanical devices in my display tank it's worth the extra noise, electrical costs and plumbing cost to me. As you mentioned people have different schools of thought.

[lastlight]

Yeah it's a RD2000 and is a skimmer pump.

I was under the impression the pumps were practically noiseless and myself and others have been suprised to find this isn't always the case. The issues I've read about may have primarily been skimmer pumps I can't recall. But the userbase is super small and I've personally read of enough issues in the forum to question the over-hyped quality (imo) of their pumps.

[robert]

Poseidon Pumps, formerly known as the "Velocity Water Pump" are for sure most silent pumps at the market. I used to own PS4 model, and it was dead silent. I had to put my hand on it to see if it runs. The only problem is that largest one runs only about 1000 GPH at 5' head. Getting 2 would be an option, especially if you are noise freak as I'm. You may read more about the pump here (http://www.jlaquatics.com/product/wp-ps4/Poseidon+PS4+External+Water+Pump.html).

Cheers!

[sphelps]

Yeah it's a RD2000 and is a skimmer pump.

I was under the impression the pumps were practically noiseless and myself and others have been suprised to find this isn't always the case. The issues I've read about may have primarily been skimmer pumps I can't recall. But the userbase is super small and I've personally read of enough issues in the forum to question the over-hyped quality (imo) of their pumps.
Skimmers are a funny thing, honestly no matter what type of skimmer you have you will have issues with it. This is because skimmer performance is based on so many variables we can't even begin to explain them. For example if I put my hand in my tank for a just a couple seconds my skimmer will stop working properly for a few minutes, and that's just one example. I use to build custom skimmers which replicated BKs but I soon quit because of the issues I had to deal with. I use to test the crap out of them and they would work just fine but as soon as the customer would get it, nothing but problems. I also run a BK skimmer and it is certainly the best skimmer I've used and certainly the quietest but it still makes noise, just less than everything else.

As far as price is concerned I honestly don't think you could make the same products for less. I work in manufacturing and machine design, I know what CNC machining costs and what would be involved in making these products, honestly the price isn't that bad and the quality is better than anything else. The problem is that not everyone sees the need for the extra quality, for example their tolerance is 0.005mm!! That is absolutely ridiculous but it sure is cool. If I asked our machine shop to do that they would laugh at first and then come up with a quote so high we would never go through with it.

I don't think the user base is very small, the Canadian distributor can't even keep these pumps in stock, they are usually sold before they arrive. It took about 5 months to get mine. The thing is you don't generally hear positive feedback, but you certainly hear negative. In addition when people pay more they expect more however the relationship isn't linear but rather exponential. For example Hyundai owners don't complain very much about their cars but BMW owners complain all the time. Price aside, BMW is a better car but yet you actually hear more complaints about BMW than you do about Hyundai. It's a funny thing but it's human nature. Nobody is going to take the time to post on such a forum saying "Hey my pump is working great, no issues what so ever".

So skimmers aside, the RD return pump is a good pump and to me, well worth the money. It might not be for everyone but if you care more about noise and quality over price a RD pump may be for you :razz:

[Canadian]

A good point but I see more to a sump than a skimmer. A higher return increases tank flow and reduces the demand for supplemental in tank flow, a big plus in my books. Also more flow increases surface tension and reduces scum build up in the display, it will also keep things suspended longer and filter more out of the display sending it to the sump quicker. Sumps can also hold mechanical filtration like socks and floss and chemical like carbon. These can benefit from higher flow. Finally things like heaters and pumps will work better with an increased convective heat transfer effect.

You don't have to run high flow but there are certainly benefits to it.

Again, a matter of personal preference but running a retun pump to provide circulation in the display tends to be woefully inefficient with respect to the amount of energy used and subsequently dumped back into the tank or atmosphere in the form of heat.

[sphelps]

Again, a matter of personal preference but running a retun pump to provide circulation in the display tends to be woefully inefficient with respect to the amount of energy used and subsequently dumped back into the tank or atmosphere in the form of heat.
Correct in certain circumstances but not always, more often than not a single large pump is more efficient than multiple smaller pumps.

But again yes it's how you look at it, my main point was there are certainly advantages but that's not to say there aren't disadvantages as well. None of the advantages I listed related to efficiency and that's mostly because efficiency is closely tied to money.

[albert_dao]

It's a funny thing but it's human nature. Nobody is going to take the time to post on such a forum saying "Hey my pump is working great, no issues what so ever".


LOL!!!! My God, you hit that nail so far through the plank it came out the other side.

*thumbs up

[tlo]

thank you all so much for your opinions and experiences. I am leaning towards a red dragon, but they are soooo pricey. If they really are as quiet as they are made out to be it will be worth it. I am very noise sensitive and what most people tune out as background "white noise" drives me crazy.

[golf nut]

Obviously there are different schools of though on this but I don't see the point in running a return pump at a rate greater than what your skimmer can accommodate. It would be a complete waste of hydro. I'd run the smallest return pump you can to meet your head loss needs to keep up with your skimmer and only use propeller pumps for flow in the display and even one in the sump to keep detritus from collecting.

Perfect

At least somebody understands what is required for a sump return.

If you ask a reputable skimmer mfg they will tell you to use a sump pump of the same value as the skimmers capacity, ie if you purchase a skimmer for a 400 gallon system it performs at its best at 400 gph passing across it, any more and its performance will be depleted. The 10 times turnover rate isn't correct if the tank is skimmed properly.

[golf nut]

for example their tolerance is 0.005mm!!

.00019" two tenths of a thou on a skimmer?

[sphelps]

Perfect

At least somebody understands what is required for a sump return.

If you ask a reputable skimmer mfg they will tell you to use a sump pump of the same value as the skimmers capacity, ie if you purchase a skimmer for a 400 gallon system it performs at its best at 400 gph passing across it, any more and its performance will be depleted. The 10 times turnover rate isn't correct if the tank is skimmed properly.
What's required can be very different from what's best or best for certain people. Also the return rate is independent from the skimmer rate. A sump simply extends the display tank, it's the same as putting a skimmer right in the display besides the effect of the overflow. In fact if anything a higher return would result in more surface water in the sump at all times. I can't see how more or less return flow, compared to skimmer flow, would greatly effect skimmer performance. Unless you have it setup some special way, the skimmer isn't skimming 100% of the water that passes by it, and no matter what the flow rate, the % of water skimmed is the same over a given time frame. The only slight improvement here would actually result from more flow, a higher sump turnover would result in less water being recycled through the skimmer. Like previously stated it's a matter of preference, both low and high flow have there advantages but it's a preference not a requirement. There are obviously limits but the range is large. One more reason I see more being better is matching the flow doesn't actually make sense if you look at the numbers. My skimmer for example flows 4000L/h and it's rated for tanks up to 3000L, hmmm so the "required" flow results in a turn over of 1.3 :confused:

Food for thought: I design and manufacture load cells and weighing systems yet I personally don't use any of them. If I was looking for advice on anything regarding it's installation and real life performance I'd ask the people using them.



.00019" two tenths of a thou on a skimmer?
That's what's stated regarding the RD pumps, not sure about the skimmer. Keep in mind it likely referring to components relating to the bearings or shafts but it still demonstrates quality.

[sphelps]

thank you all so much for your opinions and experiences. I am leaning towards a red dragon, but they are soooo pricey. If they really are as quiet as they are made out to be it will be worth it. I am very noise sensitive and what most people tune out as background "white noise" drives me crazy.
You could try and find someone local who has one and take a listen for yourself. Even if someone has a BK skimmer, disconnect the air line and you'll get the idea. I'm pretty picky on noise as well and my stand is currently wide open, all I can hear is the skimmer. the pump is very quiet in my books but like you said everyone is different, however I don't think you'll find anything quieter which most people who have compared them would agree on.

One more thing that sold me when I was considering was the fact that these pumps can be used internal! Not much else in comparable flow rate can do that. Running a pump internally usually results in a lower noise level. I ran mine external in the end and I'm glad I did but I always have the option to switch.

[lastlight]

Sphelps what you said about people only posting when they have something to compalin about...very true but true for both Sequence and RD users so I'd think that's a moot point. What you said about bmw owners vs hyundai owners however IS very relevant and a great point.

I expected a lot when I bought my BK and I felt let down. I'm sure it's going to skim just great but the pump itself seemed loud to me. I'm the sort of person that disconnects the power to the tv in my bedroom at night because I can hear high pitched noises my wife can't. I'm fussy about noise. I also agree it makes noise but less than anything else.

Having said all of this though I think I would have gotten a RD return pump if servicing these pumps and getting replacement parts wasn't so difficult and time-consuming. That's just part of owning these fancy foreign things which I understand.

[golf nut]

Food for thought: I design and manufacture load cells and weighing systems yet I personally don't use any of them. If I was looking for advice on anything regarding it's installation and real life performance I'd ask the people using them.






Please tell me you are kidding, you design something and sell something that you would ask the end user about because you don't know?

My granny has an Audi, she bought it on their 24 Le mans performance, not because it comes in a nice pearl white shade, they don't ask her to drive it around the track and ask for input.

[sphelps]

Please tell me you are kidding, you design something and sell something that you would ask the end user about because you don't know?

My granny has an Audi, she bought it on their 24 Le mans performance, not because it comes in a nice pearl white shade, they don't ask her to drive it around the track and ask for input.
Sorry but that's real life, we can do all kinds of tests but they will always be based on laboratory conditions. Most companies and people would call that good enough and act like they know everything. However some companies go the extra mine and provide perks to qualified customers in return for valuable feedback which provides more information for more accurate specifications and further advancement. Also I may design one component for a crane or power plant but I'm no expert on cranes or power plants.

I was only suggesting that the manufacturer isn't always the best source for certain information, I didn't say your grandma was either but I can assure you someone drove that car around the track and it wasn't the manufacturer.

[golf nut]

Also I may design one component for a crane or power plant but I'm no expert on cranes or power plants.

I was only suggesting that the manufacturer isn't always the best source for certain information, I didn't say your grandma was either but I can assure you someone drove that car around the track and it wasn't the manufacturer.

Considering that we typically call the manufacturer if we need information I would hope that they have enough experience, or feedback to reliably answer my questions, yet you choose to ignore their recommendations or at least fluff them off.

I will advise my granny to stay away from cranes and power plants.

[sphelps]

Considering that we typically call the manufacturer if we need information I would hope that they have enough experience, or feedback to reliably answer my questions, yet you choose to ignore their recommendations or at least fluff them off.

I will advise my granny to stay away from cranes and power plants.
Now you're just being silly, trying to twist words to your liking. First of all it was "food for thought" which means something to think about, but you chose to bring the whole thread off topic in an attempt to find holes in something that doesn't have any. Second that's not what I said at all, but I did say the exact opposite.
Maybe, just maybe a skimmer manufacturer doesn't know what size return pump you should run on your tank, that's all I was saying from the start. After all they don't usually make return pumps or full aquarium systems but rather a single component. Plus it seems some people already disagree with the ratings provided by such manufacturers, so why would you think they would be experts on other components?

If you ask a reputable skimmer mfg they will tell you to use a sump pump of the same value as the skimmers capacity, ie if you purchase a skimmer for a 400 gallon system it performs at its best at 400 gph passing across it, any more and its performance will be depleted. The 10 times turnover rate isn't correct if the tank is skimmed properly.
BK will tell you in a heartbeat that you can overdo skimming by buying a unit that is oversize, it simply doesn't work, or should I say doesn't work properly.

[golf nut]

Now you're just being silly, trying to twist words to your liking. First of all it was "food for thought" which means something to think about, but you chose to bring the whole thread off topic in an attempt to find holes in something that doesn't have any. Second that's not what I said at all, but I did say the exact opposite.
Maybe, just maybe a skimmer manufacturer doesn't know what size return pump you should run on your tank, that's all I was saying from the start. After all they don't usually make return pumps or full aquarium systems but rather a single component. Plus it seems some people already disagree with the ratings provided by such manufacturers, so why would you think they would be experts on other components?The OP requested a quiet return pump, I asked what was the reason for such a large amount of flow(read noisy).and backed up the statement regarding what the skimmer mfg suggested the ideal pump size would be.

Your answer was that the manufacturer was no expert, you continue to push high sump turnover rates and consequently ignore the manufactures suggestions, if the OP used a pump of the correct size he would not have the noise issue he is getting nor an expensive bill to purchase or operate such a large pump as you are suggesting.




,

[mr.wilson]

Red Dragon pumps are quiet, but not worth paying $900 for. It's a $10 wholesale Laguna pond pump with a custom volute (shroud & impeller).

They fall short on pressure, but would work fine for a sump return. The motor is designed to be water cooled, so you may have excessive heat transfer and subsequently a shorter pump life.

[sphelps]

The OP requested a quiet return pump, I asked what was the reason for such a large amount of flow(read noisy).and backed up the statement regarding what the skimmer mfg suggested the ideal pump size would be.

Your answer was that the manufacturer was no expert, you continue to push high sump turnover rates and consequently ignore the manufactures suggestions, if the OP used a pump of the correct size he would not have the noise issue he is getting nor an expensive bill to purchase or operate such a large pump as you are suggesting.

That's just it, the guy wanted a quiet return pump with a given flow and price was no object. I didn't push high flow, it was already requested. I never said low flow was a bad thing but rather advantages exist for both so it comes down to personal preference. If anyone is pushing it's you dude, not me. I don't know why you're making this personal.

[sphelps]

Red Dragon pumps are quiet, but not worth paying $900 for. It's a $10 wholesale Laguna pond pump with a custom volute (shroud & impeller).

They fall short on pressure, but would work fine for a sump return. The motor is designed to be water cooled, so you may have excessive heat transfer and subsequently a shorter pump life.
While the motors are made by Hagen, they are made specifically for RD, they are not standard Laguna pumps, they just have the same motor housings for obvious reasons. All that custom stuff is what you're paying for; they put in things that other pumps simply don't have like carbide bearings, titanium shafts, de-liming bypass (which reduces heat and lime build up on impeller), and high efficiency motors. Last time I checked water cooled was better than air cooled and these pumps certainly don't run hot, at least 50 degrees cooler than the Darts I previously owned. In addition these pumps can be run internal which no other pump of the same flow rating can do.

It's certainly not cheap but it's not a rip off either, if someone could make these for what some assume, I assure there would be a few more competitors on the market. These pumps are not for everyone but for some the extra money is justified.

[mr.wilson]

While the motors are made by Hagen, they are made specifically for RD, they are not standard Laguna pumps, they just have the same motor housings for obvious reasons. All that custom stuff is what you're paying for; they put in things that other pumps simply don't have like carbide bearings, titanium shafts, de-liming bypass (which reduces heat and lime build up on impeller), and high efficiency motors. Last time I checked water cooled was better than air cooled and these pumps certainly don't run hot, at least 50 degrees cooler than the Darts I previously owned. In addition these pumps can be run internal which no other pump of the same flow rating can do.

It's certainly not cheap but it's not a rip off either, if someone could make these for what some assume, I assure there would be a few more competitors on the market. These pumps are not for everyone but for some the extra money is justified.

The Eheim Hobby Pump is equally as good as the Red Dragon, but unfortunately they aren't offered in higher output. The Aqua-Medic Ocean Runners are also quiet and reliable, but limited to 6500LPH and the impeller shroud is made of brittle plastic. The Deltec Intervall series is supposed to be very good, but Deltec USA doesn't supply them. http://www.deltec-aquaristic.com/

Until something better (stronger) comes along, I use Poseidon pumps for return pumps even if I have to use two of them. They are available as pressure or volume pumps, dead quiet, and no significant heat transfer. They run at about 130F externally.

[sphelps]

The Eheim Hobby Pump is equally as good as the Red Dragon, but unfortunately they aren't offered in higher output. The Aqua-Medic Ocean Runners are also quiet and reliable, but limited to 6500LPH and the impeller shroud is made of brittle plastic. The Deltec Intervall series is supposed to be very good, but Deltec USA doesn't supply them. http://www.deltec-aquaristic.com/

Until something better (stronger) comes along, I use Poseidon pumps for return pumps even if I have to use two of them. They are available as pressure or volume pumps, dead quiet, and no significant heat transfer. They run at about 130F externally.
Absolutely, the eheims are good pumps but unfortunately don't meet everyone's flow requirements like you said. I don't have experience with the other pumps you mentioned but maybe it's hard to find a real comparison because it doesn't exist. Making a high flow magnetically driven pump that runs quiet and cool just might be difficult which would explain why prices are high.

[mr.wilson]

Absolutely, the eheims are good pumps but unfortunately don't meet everyone's flow requirements like you said. I don't have experience with the other pumps you mentioned but maybe it's hard to find a real comparison because it doesn't exist. Making a high flow magnetically driven pump that runs quiet and cool just might be difficult which would explain why prices are high.

I think it's the low demand for such pumps. While I'm sure your local distributor can't keep Red Dragon pumps in stock, it's still a tiny market compared to the industrial pumps we currently use in the hobby.

[sphelps]

I think it's the low demand for such pumps. While I'm sure your local distributor can't keep Red Dragon pumps in stock, it's still a tiny market compared to the industrial pumps we currently use in the hobby.
True but I believe it's a small market because prices are high not the opposite, just like any other high end product. It's certainly not for everybody, people have to make their own decisions which products will best fit their needs.

[sphelps]

Mr. Wilson got me curious when he mentioned the temperature his pump ran at so I checked mine tonight.

http://i11.photobucket.com/albums/a174/sphelps/photo-2.jpg

It's the RD 6.5m3, hottest part was at the top back corner, was around 92F but dropped to 90.8F when I snapped the shot.

[mr.wilson]

Mr. Wilson got me curious when he mentioned the temperature his pump ran at so I checked mine tonight.

http://i11.photobucket.com/albums/a174/sphelps/photo-2.jpg

It's the RD 6.5m3, hottest part was at the top back corner, was around 92F but dropped to 90.8F when I snapped the shot.

I guess that puts your turnover rate at about 15x with the head loss :wink:

[sphelps]

I guess that puts your turnover rate at about 15x with the head loss :wink:

I believe it's actually just over 10x

Here's the pump curve for the RD 6.5m3 and 8.5m3, some people have asked me about it. Sorry but you'll have to convert :razz:

http://english.royal-exclusiv.de/Meerwasser_Aquarium/lkurve6.gif

http://english.royal-exclusiv.de/Meerwasser_Aquarium/lkurve8.gif

[Joe Reefer]

I have to disagree, Red Dragon pumps are far superior to Eheim. If you have the money for a Red Dragon then buy one, you wont be disappointed. That said, poseidon makes a very quiet pump also, but you are limited to lower flow rates and massive amounts of heat transfer.


The Eheim Hobby Pump is equally as good as the Red Dragon, but unfortunately they aren't offered in higher output. The Aqua-Medic Ocean Runners are also quiet and reliable, but limited to 6500LPH and the impeller shroud is made of brittle plastic. The Deltec Intervall series is supposed to be very good, but Deltec USA doesn't supply them. http://www.deltec-aquaristic.com/

Until something better (stronger) comes along, I use Poseidon pumps for return pumps even if I have to use two of them. They are available as pressure or volume pumps, dead quiet, and no significant heat transfer. They run at about 130F externally.

[Froggie]

Mind the motor housing surface temperature is deceiving. It's definitely not the best indication of heat transfer to the tank water. The anti-calcium loop (ie. water jacket) provides active cooling for the motor by transferring the heat directly to fluid.

I've never owned a Red Dragon pump, nor do I appreciate the price, but it's nice to see a little more rigor applied to the design of hobby pumps. That said the mystique behind them is a bit much for my tastes. There are certain realities that need to be accepted as to the maximum efficiency of an electric motor, or its heat output. It's not an especially detailed set of calculations...

My recommendation for a quiet return pump? Buy a recommended and medium priced pump, create a damping base and decouple the discharge from the return piping with some form of expansion joint.

Mr. Wilson got me curious when he mentioned the temperature his pump ran at so I checked mine tonight.

http://i11.photobucket.com/albums/a174/sphelps/photo-2.jpg

It's the RD 6.5m3, hottest part was at the top back corner, was around 92F but dropped to 90.8F when I snapped the shot.

[mr.wilson]

The Poseidon/Velocity pump has a very hot external temperature, but this because the heat is on the outside, not the inside. Poseidon proved to have less heat transfer than Iwaki during testing. The heat transfer for a 50 gallon tank was not measurable. A heat sink would be a good addition to the Poseidon nonetheless. I like that it doesn't have a fan, nor do I think it needs it.

The older Red Dragon pumps have poor head pressure. Losing more than 1/3 of the flow with modest head pressure is disappointing for that kind of money. I don't now much about the new line of Red Dragon pumps, but I would consider using them if they were good quality even if they are expensive. For me it's more of a value for money issue than actual cost.