Why do I get a short life from my air pump diaphrams

Hi, To increase life of rubber diaphragms, the unit must have back pressure. How does one create back pressure?

Answer: 

It must not run OPEN, in other words, without pipes and air stones. It must work again some restriction. It normally makes a loud noise.

AT the same time, it must also not work too hard agains restiction like too few small air stones or stones placed too deep in a tank or pond. Then the pump gets hot.

To ensure long life of the diaphragms, the pump must not run too HOT. Too few air stones for its rating.
Test for this is that the pump must run "cool" by testing the heat with your hand. If you cannot touch it with your bare hand it is too hot. (Always test with the back of your hand first, it resonable, test with the inside of your hand.)

The best point to run a pump beteen 20-60% of the rated pressure. Look at the work curve on the box.

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