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Aquarium Supplies
Home » Saltwater Aquarium Supplies  » Water Pumps  » External  » Up to 1000 GPH  »  Iwaki MD40RLT Water Pump (Japanese Motor)
Iwaki MD40RLT Water Pump (Japanese Motor)

Iwaki MD40RLT Water Pump (Japanese Motor)

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Iwaki MD40RLT Water Pump (Japanese Motor) Information

Product Manuals & Documentation

Magnetic water pumps. Magnetic driven. Sealess pumps for use on fresh or saltwater aquariums. Low heat exchange. 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: MD40RLT*
Inlet(MPT)/Outlet(MPT): 3/4"/3/4"
Flow Rate @ 4` Head: 750 GPH
Max Head ft: 21.3

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.

Note: Power cord plug NOT included.

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 MD40RLT Water Pump (Japanese Motor) Reviews

Average Rating
(68 reviews)
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of 7

Iwaki MD30

Reviewers Rating Excellent!

Posted: 2/28/2014 from WHARTON, NJ UNITED STATES
4.5 5
Experience Level: Intermediate

Comments: Great pump, incredibly quiet and plenty strong to run my ETSS Skimmer which was recommended to run with the MD40. Only draw back is it does get very hot, but I'll take the heat over noise any day. I also purchased the MDX40 which works great but because of the fan it is a little noisy!! All in all you can't beat these pumps, well worth the money!!

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


Reviewers Rating Excellent!

4.5 5
Experience Level: Intermediate

Comments: Excellent pump, runs great. Very quiet.

Did you find this review helpful? Yes No

canadians watch out!

Reviewers Rating Excellent!

Posted: 12/19/2013 from CALGARY, CANADA
5.0 5
Experience Level: Intermediate

Comments: Fantastic pump! if you are looking at it you already know. i live in canada and upon arrival ups hit me with a $72 import charge. not much value buying from the states after that imo. just a heads up to my canadian friends.

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


Reviewers Rating Excellent!

Posted: 10/21/2013 from SAINT PAUL, MN UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: There probably isn't a need to review Iwaki MD pumps. They've been around a long time and everyone knows they are well built. I have the 30RLT. The 20s and 30s don't have fans, so they run hot to the touch, but much quieter than the 40s and up. Pressure rated and likely to run unnoticed for years to come, it's a great pump. I also like knowing that replacement parts are easily found should I need them.

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

Good Strong Dependable Pump

Reviewers Rating Excellent!

Posted: 9/6/2013 from OR UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: The Iwaki MD70 pump is a good quality and well designed pump, and circulates water quite well within the aquarium. It is however a bit on the loud side, so if you are looking for a quiet pump I would probably choose another. If you are wanting this pump to work with a large canister filter, it will certainly do the job with ease and can of course handle back pressure well. It has performed flawless for me thus far and I would certainly recommend this pump to anyone who wants quality & dependability!

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

Amazing reliability!

Reviewers Rating Excellent!

Posted: 8/14/2013 from SPRING, TX UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I own an Iwaki MD-20RLXT pump that has been running my 90 gal tank for 26 yrs. I am debating on whether to rebuild it with a new impeller, front and back case, and o-ring. Parts and shipping total is 134.79. I have been very happy with this pump and calculated that it has performed at least 43046640000 revolutions. That’s over 43 BILLION revolutions! Should I go ahead and buy a new pump for $60.90 more? I think I just answered my own question!

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


Reviewers Rating Average

Posted: 8/14/2013 from Stuart, FL UNITED STATES
2.5 5
Experience Level: Expert

Comments: Fan rubs on housing during start up. Sounds like something is stuck in fan, very loud then stops clanging when at full speed. Overall pump runs loud when in use compaired to the little giants. Time will tell on the reliability.

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Reviewers Rating Excellent!

Posted: 6/2/2013 from DIAMOND BAR, CA UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I am another one of the happy hobbyist with my Iwaki MD-30 RT return pump. My biggest problem prior to installing this exterior pump was heat and very little space in the sump for another pump, Iwaki solved that problem expertly. I've been running this pump for the past several years with no issue. Their is a constant low hum that I no longer pay any attention to. This is a very good investment.

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Excellant Pumps

Reviewers Rating Excellent!

Posted: 5/3/2013 from PEARLAND, TX UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I have had this pump as well as a 30RLT running on my 200 gal marine tank for 13 years straight now. These pumps are beasts.. Never an issue with either one of them. Best investment I made for my system. I highly recommend these pumps.

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

Great Pump

Reviewers Rating Excellent!

Posted: 4/13/2013 from HIALEAH, FL UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I've had this pump now on my 92 gallon corner unit for about 6 months. This pump is a work horse! Great quality build and relatively quiet considering its application, placement a work load. I would recommend this pump to anyone and would absolutely use it on any tank I have.

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

of 7

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