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Blue Diamond Pumps Blue Diamond ET 40 Septic or Pond Linear Diaphragm Air Pump

Based on 276 reviews
Condition: New
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$147.00

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Availability: In Stock.
Fulfilled by Amazon

Arrives Thursday, Nov 5
Order within 22 hours and 18 minutes

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At a glance

Condition
New
Model
ET40
Dimensions
8.66"L x 6.1"W x 7.48"H
Weight
5 lb
Color
Blue,Bronze
Power Source
Electricity
Air Flow Capacity
1.41 cfm

Features 5

  • BOOSTS SEPTIC WASTE DECOMPOSITION: By adding clean, oil free oxygen to septic system wastewater, Blue Diamond's Enviro ET 40 air pump encourages aerobic bacteria to decompose. Its weatherproof and sturdy design make it an excellent wastewater pump. It is also effective in a pond.
  • OPERATES QUIETLY: This air pump produces little sound, as low as 35 decibels. It uses 30 watts of electricity and has a maximum air flow of 1.41 cubic feet per minute. Its maximum pressure is 0.15 bar.
  • EASY TO INSTALL AND SERVICE: Simple to put in place, this pump comes complete with a 3/8" ID bronze fitting. It is easily serviced with replaceable diaphragm kits (sold separately) for a long life.
  • BACKED BY A 2-YEAR MANUFACTURER WARRANTY - MADE TO LAST: In addition to being weatherproof, this durable pump features a specially formulated material for its linear diaphragm. Constructed to last, the pump has a 2 year warranty from its manufacturer.

Description

MAKES POND WATER BETTER The Blue Diamond Enviro ET40 Koi Pond Summer Aeration and Winter Deicer Linear Air Pump adds oxygen to a pond, water garden or other water feature throughout the year in all weather conditions. The increase in oxygen clarifies the water and raises its quality, which helps fish, plants and other pond life. The air that the pump adds is clean and free of oil. When temperatures are freezing, the pump helps to keep ice from forming on the pond. Making little noise as it operates, the pump has a maximum air output of 1.41 cubic feet of air per minute. Its maximum pressure is 0.15 bar. It uses 30 watts of electricity. The size of its connector is 0.55 inch OD. WEATHERPROOF AND ROBUST Backed by a 2-year manufacturer's warranty, this air pump is designed to be durable. It is weatherproof, and its sturdy construction includes material specially formulated for its linear diaphragm. SIMPLE TO USE AND MAINTAIN This pump comes complete with a bronze 3/8" ID bronze fitting and is easy to set up. It is easily serviceable with replaceable diaphragm kits (sold separately) to give the pump a long life. Put the Blue Diamond Enviro ET40 Koi Pond Summer Aeration and Winter Deicer Linear Air Pump to work in your pond or septic system. Please Note: For applications requiring more than 33 ft. of tubing please contact us! Click "Add to Cart" now!

Specs 19

Color Blue,Bronze
Brand Blue Diamond Pumps
Item Weight 5 pounds
Product Dimensions 8.66"L x 6.1"W x 7.48"H
Power Source Electricity
Air Flow Capacity 1.41 cfm
Maximum Pressure 0.15 bar
Operation Mode Automatic

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Nov 5

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


nice pump, good price
Quiet and gets the job done. Using this on an aerated bottom drain at 3' depth. Provides just enough air. If pond were deeper, the next size up would be better.
Reviewed in the United States on July 22, 2021 by Honu

Great lil pump!
Great lil pump! Just as good as them big name brands, just not that big name price!
Reviewed in the United States on August 2, 2025 by Jason

Is very very Quiet!
I use it as an air pump for my septic system. I like how quiet it is since it is next to our patio. I have used the ET60 and ET80 before, ET80 was to loud next to the patio. I'm hoping the ET40 is enough air-flow and that it last 2-3 years or longer. I have only had it one month at this point.
Reviewed in the United States on March 5, 2022 by Buy Online Express

Good service
Works good, came as expected
Reviewed in the United States on February 23, 2026 by Amazon Customer

I did it !
Easy installation, good price , quiet
Reviewed in the United States on February 15, 2025 by head on straight

Great buy for the price
This came with everything I needed. New 1/2" rubber tube, clamps, and a few extra things. I hooked it up and once I connected the air tube to my septic vent I found the pump to run VERY quietly. It was a very worth while, cost effective, replacement.
Reviewed in the United States on October 19, 2019 by Steve-Oh the Great

Extremely easy to set up, great air flow on 250 gallon tote, weather proof
I used this for a 250 gallon bait tank with a root scape diffuser to make aeration. I'm extremely satisfied so far, only 4 days old. Extremely easy to install for my set up. Will update as time goes on. Highly recommended for purchase.
Reviewed in the United States on April 30, 2024 by Mark A.

Value for the money
Reasonable replacement for my Thompson AP40 aerobic septic pump. Would have been nice if the outlet had a tapped hole for the pressure sensing fitting. I drilled and tapped my own - works a charm
Reviewed in the United States on September 19, 2023 by Colin R. Francis
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