In our experience diffusers ...
Published by Gerd Teunissen, technical director at INTERAGUA, Lda.
In our experience diffusers with silicone membranes last longer and maintain their high performance. That's why we apply them in our SBR systems, even in round tanks.
The tube diffusers from OTT (Germany) have several length options and can be easily adapted to most tank sizes.
And I agree with Michael Martin, deeper tanks give higher efficiency with a denser bottom coverage by the diffusers.