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Aquarium Supplies
Home » Saltwater Aquarium Supplies  » Water Pumps  » External  » Up to 1000 GPH  »  Iwaki WMD20RLT Water Pump - (American Motor)
Iwaki WMD20RLT Water Pump - (American Motor)

Iwaki WMD20RLT Water Pump - (American Motor)

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Iwaki WMD20RLT Water Pump - (American Motor) Information

Product Manuals & Documentation

Magnetic water pumps. Magnetic driven. Sealess pumps for use on fresh or saltwater aquariums. Low heat exchange and quiet in operation. Highly durable design. WMD pumps have American Made Motors. MD pumps have Japanese Made Motors. RLT pumps are for pressure applications. RLXT pumps are for circulation and wet/dry return.

Iwaki Walchem magnetic drive pumps will run longer, quieter and cooler than any traditional mag drive. Extraordinarily high efficiencies make WMD & MD the clear choice in almost every process, recirculation or transfer application.

Unique internal Cooling Circuit
Creates a positive, forced cooling path, lubricating bearing surfaces and actively purging gases & heat. Unique double bearing system allows cooling circuit liquid to continually "wash" front and rear radial bearings, extending bearing life.

Precision Tolerances
Pumps can be supplied with alumina ceramic or SiC spindles, bored, turned and highly polished. This precision machined spindle forms the center of the driven magnet. Substantially reduced hydraulic noise is a major feature of all WMD/MD impellers. Great pains are taken in the molding/finishing process to eliminate tangential misalignment.

Bearings/Thrust surfaces
High lubricity fluoropolymer bearings minimize mechanical losses typical of conventional mag drive pumps. High purity SiC radial bearings handle the most aggressive ultrapure chemistries. PTFE front thrust surface aids hydraulic balance and minimizes flashing. Large rear thrust surface guards against axial forces caused by cavitation or gas entrapment.

Drive magnet
Dynamically balanced barium ferrite drive magnets provide best magnet torque. Die cast magnet carrier creates a flywheel effect, which adds to the magnet safety factor.

Motor matching
Offering more standard motor/pump configurations than other manufacturers offer for tailored pump applications. Premium, high efficiency motors are used throughout the line. Totally enclosed, permanent split capacitor motors are compact, cool and economical. Tolerance to voltage variation without overheating and 50/60 Hz operation allow the product to be used in a worldwide market.

Model: WMD20RLT*
Inlet(MPT)/Outlet(MPT): 3/4"/3/4"
Flow Rate @ 4` Head: 420 GPH
Max Head ft: 14.1

In the unlikely event there are any problems with Iwaki water pumps or warranty work is needed at some point, please contact Iwaki directly at 508.429.1440 for an RGA. Do NOT send a pump back to Iwaki without an RGA number. Please contact us for any assistance you may need in this unlikely situation.

Manufacturer Info

Iwaki America Inc.
Iwaki America Inc. of Holliston, Massachusetts, is a joint venture which grew from a 15 year association between Walchem Corp. of Holliston, MA and Iwaki Co. Ltd. of Tokyo, Japan. Combining Walchem`s 30 years of chemical injection and control experience with Iwaki`s 50 years of pump design engineering, Iwaki America offers the best chemical handling equipment for use in Process, O.E.M., Industrial and Semiconductor applications. Iwaki America, along with Walchem Corporation and Terracon Corporation comprise the Walchem Group.

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Iwaki WMD20RLT Water Pump - (American Motor) Reviews

Average Rating
(23 reviews)
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of 3

First time Iwaki owner

Reviewers Rating Excellent!

Posted: 9/6/2012 from NEWBURY PARK, CA UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I have used Little Giant in the past to run my canister filter and was happy with them. This Iwaki seems to be a great alternative, its quiet, provides good power and runs cool.

2 of 3 People found this review helpful, did you? Yes No

Magnetic Drive Water Pump

Reviewers Rating Excellent!

5.0 5
Experience Level: Intermediate

Comments: This is the second one I have owned for a 1000g pond. The first one lasted 10 years of non-stop operation through all seasons . . . and it quit because it ran dry when the pond filter became clogged. A very impressive unit!

1 of 1 People found this review helpful, did you? Yes No

Solid as a rock.

Reviewers Rating Excellent!

Posted: 10/1/2011 from LUBBOCK, TX UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: This is one well made pump. No plastic here. Nylon connection fittings, metal housing. I have not had it long but am very impressed with the construction and performance at this point.

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Good not Great

Reviewers Rating Great

Posted: 8/13/2011 from ATWATER, CA UNITED STATES
3.5 5
Experience Level: Beginner

Comments: I'm new to a using a sump so I didn't really know what pump to get, so I read the reviews and seen the specs and I have to say it's too powerful for my 55 gal aquarium. It's a 3/4" inflow/ outflow pump that I use with my 1" overflow drain which is gravity driven. When I first put my sump together it drain my 20 gal sump in about 45 seconds and your heard this god awful slurping sound because my overflow drain can't keep up. So I solved my problem by installing a ball valve after my pump going to my tank to regulate my sump water level. I would of rated this pump with more stars but my wife was irate because the NOISE that comes from this pump is extremely LOUD! Eventhough I have my pump mounted on my stand with rubber washers with my doors closed it still sounds like my wife is vacuuming in the other room all day. Hope this helps.

2 of 2 People found this review helpful, did you? Yes No

wmd 20 rlxt

Reviewers Rating Excellent!

Posted: 3/17/2011 from VERO BEACH, FL UNITED STATES
5.0 5
Experience Level: Expert

Comments: I purchased this pump over 10 yrs. ago and it is still running great. I have never had to do anything to it. I have a 125 Cichlid tank, with a wet/dry filter system! The pump made some noise sitting on the base of the cabinet, so I hung it in the air with a piece of wire,eliminating my noise problem.It"s a GREAT PUMP !!

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Reviewers Rating Great

Posted: 1/9/2011 from BROOKLYN, NY UNITED STATES
4.0 5
Experience Level: Intermediate

Comments: This pump Is very quiet and very easy to install. On a scale of 1 too 10 I give it A 8 plus.

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good pump

Reviewers Rating Great

Posted: 3/10/2010 from WILMINGTON, MA UNITED STATES
4.0 5
Experience Level: Intermediate

Comments: so far so good. 70g tall with 20g tall sump. seems powerfull enough to move everything in my tank. no powerheads but getting great movement. very quiet but gets a little hot. 151 degrees F on the outer housing using an infrared laser gun. I dont have any other pump to compair so that temp may be normal. i give it an 8 out of 10.

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not at loud

Reviewers Rating Excellent!

Posted: 3/6/2010 from Pikeville, KY UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: good pump and not that loud compare to japan make . if you like Iwaki then buy it and save your self some money

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Iwaki wmd 40rlxt

Reviewers Rating Excellent!

Posted: 1/1/2010 from TULSA, OK UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: Great pump. Very powerful and quiet.

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Iwaki WMD external pump

Reviewers Rating Excellent!

Posted: 11/14/2009 from Plantation, FL UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: This is my second Iwakl brand (Americamn made) pump. I am again, very pleased with its performance. My original pump was up and running for about 11 years. It is reasonably quiet and pretty much maintanence free.

3 of 3 People found this review helpful, did you? Yes No

of 3

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