quietest return pump

[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]

Originally Posted by 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.

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]

Originally Posted by sphelps

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]

Originally Posted by mr.wilson

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]

Originally Posted by sphelps

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]

Originally Posted by mr.wilson

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.



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]

Originally Posted by sphelps

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



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

[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.

Originally Posted by sphelps

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



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.

[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.

Originally Posted by mr.wilson

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.