best pump for 225 gal tank?

[bellaroxio]

My Iwaki is going out (fine mists of air bubbles). May I ask what is the best/long lasting replacement? Thanks so much

 

[meowzer]

Is this a return pump....a skimmer pump????
I have a mag1800 for a return pump in my sump/fuge for my 225g

 

[scsinet]

Frankly I'd consider changing an Iwaki for anything but a Sequence to be a downgrade.
Any idea where the bubbles are coming from? I assume you've checked to make sure the pump isn't cavitating. The only thing I can think of is if the impeller chamber is leaking, that may just be a matter of tightening the bolts (CAREFULLY) or replacing the o-rings.
Just about every component of an Iwaki is available as replacement parts...