Adding a secondary filter - mainly for polishing

[Sleeveless]

On my 75g, I have a Fluval FX4 with the intake/output on the left side of the tank. The outputs face 1 to fire to the right side of the tank and the 2nd 90 degrees off that one to fire to the front. I have Purigen and polishing media in the fx4, but if there is ever a need to treat the tank and the larger need to replace those polishing pads every 30 days as they build up with quickly I was thinking of adding a second, HOB filter on the right side of the tank to just hold filter floss and purigen. Question is, if I go this route, should I spec a filter for the same level of turnover as my primary or is something a little smaller sufficient. Example: I was looking at the Fluval AC50 which is a little under for a 75g.

Just looking for some opinions since I've seen postings on FB about this topic, but never asked the question about sizing.

 

[Rusty_Shackleford]

I probably wouldn't go through the expense of another Fluval, especially if you're looking for some to just polish the water.

I would do this. Run it for 24 hours once in a while to polish the water and then take it out till next time.

Amazon.com

 

[seangee]

SInce you don't need more filtration capacity isn't really a factor. More important is flow and ensuring you don't introduce unwanted turbulance.
I have no idea what fish you have or what the tank looks like but do you actually need purigen and polishing pads running all the time? My tanks are crystal clear with just sponge. If I need to clear something unusual I will take action, but adding a filter just because the pads are dirty seems overkill when (IMHO) they aren't really neccessary.

 

[Magnum Man]

the linked filters were some of the 1st filters I tried, when I got back onto tanks a few years ago... mostly because I used mostly Marineland Magnums previously... I hated those filters, as they require you to put them fully into the tank...the function was OK, except the diverter flap, was a weak link... but they were a huge eye sore... I like to hide any of the normal hardware, and there as just no hiding those... I have 2 that are in my old equipment tote....

 

[Rusty_Shackleford]

the linked filters were some of the 1st filters I tried, when I got back onto tanks a few years ago... mostly because I used mostly Marineland Magnums previously... I hated those filters, as they require you to put them fully into the tank...the function was OK, except the diverter flap, was a weak link... but they were a huge eye sore... I like to hide any of the normal hardware, and there as just no hiding those... I have 2 that are in my old equipment tote....

I agree it would be an eyesore permanently in the tank. I thought the OP was looking for a temporary or once in a while polisher.

 

[Sleeveless]

I probably wouldn't go through the expense of another Fluval, especially if you're looking for some to just polish the water.

I would do this. Run it for 24 hours once in a while to polish the water and then take it out till next time.

Amazon.com

The AC50 is $53 right now and I get 15% off with the Petco program I subscribe to so was just looking in that direction. Where the cost would get go up is the AC100 which is more expensive, but spec'ed for the tank size. If I don't need that high of a turnover due to the limited use of the secondary I'd go with the smaller. That Marineland filter looks pretty cool as well though.

 

[Sleeveless]

I agree it would be an eyesore permanently in the tank. I thought the OP was looking for a temporary or once in a while polisher.

I would run it 24/7. It would also help a dead zone I have on that side of the tank where some algae builds up (thats a whole different topic that is getting better though)