Hi Rafel,
Sorry, I took a couple days off of Q&A duty..........LOL
Q1. I have read that most will recommend to have 2x diffuser for a 180g tank. Now if I were to use Mazzei injector, do I have to use 2x Mazzei or is it that efficient that I only need one?
Just one should work. I have a 180 as well as Tom and only 1 mazzei is needed.
Caveat of course is that it is properly powered and sized for your application/configuration.
Q2. Which of the Mazzei model that is suitable for me?
I am not sure that size pump will do the job. Venturis work using pressure not flow. So a high flow mag drive pump will not do as well as say a higher pressure Iwaki that may have less flow...
You can certainly try it, but not sure if it will work. I tried running my mazzei at first on a mag 500 and than a 9.5 and still didn't do the job for me. It 'works' just not optimally and then you may think, 'oh mazzeis aren't all that' when the issue is that it was not used/configured properly.
When I finally went with a nice high pressure pump, the mazzei performance was as it should be.
I am currently using a 384 model but have also used the 584 model as well on my tank.
I am currently powering with a pan world ps250 which is a big pump... However it is also powering my two NC canisters as well.
I am pretty sure ran his mazzei on his 180 with an Iwaki 70 (I think) if that gives you a comparison.
He has since switched back to discs with no apparent detrimental effects on his tank....
Two diffusers will also work well.........