Have a Fluval Osaka 320, about 84g and a Fluval g6 filter. The G6 is strong. Flow is excelent. My tank is heavily planted with a large bio load. I change water only about monthly now rather than the weekly I used to. Parameters are fine and fish healthy.
I also don't meticulously remove all dying leaves as I used to. With that monthly change I do, but truth is I don't root through all of the java fern for instance, trimming every waning leaf.
Consequently water is clean, but does have more suspended particles than I'd like. I like easy fiddling and gadgets, so throwing an intake/outflow over the side to add some extra mechanical filtration would be more fun for me than going back to weekly changes and more scissor time.
That's the scoop. I change the mechanical cartridge of the G6 weekly, sometimes more frequently if flow declines sooner. Flow meters are nice! There's just a lot of particulates in this tank.
I have a G3 on a 33g tank and it only needs a mech cartridge change monthly if that.
That's the scoop, no real problems with the tank, I just want crystal clear water and am thinking an occasional polish with a strong temp filter would be the way. The cabinet of the Osaka setup doesnt have space for a larger filter. The G7 is stringer than the Eheim 2076 that I used prior to the G6, so even if G6 was inadequate for this setup/scale options would be limited.
I did use a magnum 250 with micron cartridge but it really didn't have the throughput to have impact as a temp augmentation.
The G series have fine mech filtration cartridges that work well, but clog quickly. I hoping to use something that turns over a lot of water and filters finely to "clear" the tank once in a while between water changes.
Thanks for input.