Blue Diamond ET Series Air Pumps are versatile pumps that can be used in aquariums, ponds and certain septic applications. The weatherproof pump has a robust and compact construction, and the main body is constructed of cast aluminum alloy.
Ther are two differenet size connections on each model.
The ET30 and ET40 each have a plain horizontal 14.0mm (0.55") O.D. outlet connection fits tight on a 1/2" I.D. tubing or loosly with a 5/8" tubing. A rubber elbow is also included. Each pump also comes with barbed fitting that threads into the threaded interior of outlet to provide a 10.0mm (0.39") O.D. barb which fits well in 3/8" I.D. tubing.
The ET60, ET80, ET100 and ET120 each have a plain horizontal 18.0mm (0.71") O.D. outlet connection fits very tightly on 5/8" I.D. tubing or loosly in 3/4" I.D. tubing. A 3/4" rubber elbow is also included. Each pump also comes with barbed fitting that threads into the threaded interior of outlet to provide a 12.0mm (0.47") O.D. barb which fits well in 1/2" I.D. tubing.
The ET50 and ET200 each have only a plain horizontal 18.0mm (0.71") O.D. outlet connection fits 3/4" I.D. tubing. A 3/4" rubber elbow is also included.
On all models where the "brass" is used to connect to a septic pump alarm, the brass is 4mm or about 1/32nd.
2 Year Warranty
This warranty does not include the diaphragm kits, which are a replaceable, wearable part (typically replaced every 12-18 months). Warranties are at the discretion of the manufacturer as to whether the damage is due to misuse or to defect.
The most common problem with this and other larger air pumps is premature diaphragm tearing due to excessive back pressure. People don't tend to understand how much air the large sized pumps produce. If an air pump is powering too small of a diffuser or too few outlets, excessive back-pressure can occur. The solution is to add a tee with a ball valve or other "bleeder valve" so that excessive air can be bled off into the atmosphere. Start with the valve completely open and slowly close it until you have the maximum output from your air diffusers without unnecessary back pressure
Important NOTE: The Blue Diamond ET series aerators are designed for relatively shallow water. The ET Series pumps have a maximum pressure threshold of 0.25 bar which is approx 8 foot of water depth. Therefore they should probably only be used in water up to 7' deep.
Note: All prices in US Dollars