MD-20RT - 492 GPH - Iwaki Japanese

Iwaki MD-20RT
Click on image to zoom
View full size image

More Views

  • Iwaki MD-20RT
  • Iwaki and Panworld External Pumps
  • Iwaki MD-20RT
  • Iwaki MD-20RT

MD-20RT - 492 GPH - Iwaki Japanese

100% Recommend this to a friend (5 of 5)

SKU: 300408

reg. $199.99

Special Price: $169.99

In Stock: 10
Please wait...
Ships tomorrow

365 Day Returns

What's This?

Preferred Reefers
Earn Up To 5% Back

Quick Overview

Why does BRS recommend this?

Anytime we need an external pump the Iwaki Japanese motors are our first choice.  There are cheaper options that work just fine, however when it comes to noise the Iwaki Japanese external pumps are class leaders and for any area where noise a concern and space is limited. The Japanese Iwaki pump is the way to go.

  • Japanese Motor

  • Max Flow: 492 GPH

  • Max Head: 14.1 Ft

  • ¾” Inlet(MPT)/ ¾ ” Outlet(MPT)

  • Max Amps: .48

  • Motor Output: 1/38 HP

Note: The Iwaki MD pumps' power cords do not come with the plug pre-spliced.


Full Details

External pump from Iwaki, the world leader in small magnetically coupled centrifugal pump technology. Japanese-made motor is designed especially for aquatic applications. Super quiet and energy efficient with less parts.

High quality external pump with years of research and development behind its design. Iwaki pumps offer high pressure rates in a durable, compact pump. Easily tailor pump applications because of the numerous motor/pump configurations. MD stands for Mag-Drive.

MD Series – Japanese Motor

  • Japanese motor is made from cast aluminum with a cast end bell
  • Japanese model uses a custom pump design specifically for aquatic applications
  • Japanese pumps run cooler to the touch and slightly quieter, due to the thicker material

Quick Compare - Iwaki MD Pumps (Japanese Motors)


Power Usage

Maximum Flow

Maximum Head


Iwaki MD-20RT


492 GPH

14.1 ft

Hose 5/8” NPT ¾”

Iwaki MD-20RXT


822 GPH

8.2 ft

Hose 1” NPT 1”

Iwaki MD-30RT


600 GPH

17.7 ft

Hose ¾” NPT ¾”

Iwaki MD-30RXT


1140 GPH

13.5 ft

Hose 1” NPT 1”

Iwaki MD-40RT


822 GPH

21.3 ft

Hose ¾” NPT ¾”

Iwaki MD-40RXT


1344 GPH

15.4 ft

Hose 1” NPT 1”

Iwaki MD-55RLT


1104 GPH

26.9 ft

Hose 1” NPT 1”

Iwaki MD-70RLT


1536 GPH

31.8 ft

Hose 1” NPT 1”

Iwaki MD-100RLT


2136 GPH

39.0 ft

Hose 1” NPT 1”


5 Items

  • Great pump! By Joshua on 5/8/2017

    Pump is super quiet. I don't even hear it at all and creates the proper amount of flow back into my tank. LOVE IT!!
  • Good Solid Pump By jwcollect on 12/14/2015

    Pump works as advertised and is very quiet. I only wish it was self-priming. Would definitely recommend it.
  • Great pump worth every penny By Matt on 4/22/2015

    I absolutely love this pump. I reconfigured a biocube 14 to utilize this bad boy and could not be happier. I installed the pump with a gete valve, backflow preventer, and a chiller. My flow is excellent even through all the components and about 8 feet of pipe. Thanks for the advice on this pump
  • nice pump By ROGERWILCO357 on 9/8/2013

    Well you get what you pay for and love the quiet pump and its longevity I have had one of these for years and after switching to another tank it sat for years then I put it on again and worked like a champ ..
  • Great Pump (quiet!) By David on 2/22/2013

    I just finished installing this pump and I could not believe how quiet it is. The demo in the video do not do justice. If this pump fits your specs...get it.


Ask a question

Product Questions

I've noticed that after 1.5 years, my 20RT is precipitating salt out the sides, indicating to me that it may be leaking. I plan to remove it and clean it soon, but if the gasket has gone out, where can I get a replacement? Is it as simple as getting a new o-ring at the hardware store, or will I need to order a part from the manufacturer?
Question by: Eric Anderson on Jun 9, 2017 11:19:00 AM
It does sound like the seals may be aging. We don't currently have replacement components for these pumps. For assistance with parts, we recommend reaching out to Iwaki directly.

Iwaki – 508-429-1440

Happy reefing!
Answer by: Zack (Admin) on Jun 13, 2017 11:19:00 PM
A lot of great information on this pump. My space is limited and would like the dimensions on the unit.
Question by: Matt Lee on Mar 14, 2016 10:23:00 AM
Great question!
This pump will have dimensions of:
8" x 4.17"x 4.19"
Feel free to let us know if you have any further questions!
Answer by: Connor (Admin) on Mar 15, 2016 3:51:00 PM