Filstar XP media...

instead of buying the expensive media at the lfs (big al's or wherever), i would go to a craft store, walmart, zellers, etc and get a big bag of the polyester batting. just make sure it says 100% polyester and doesn't have any anti-mildew agents added. a big bag should cost way less than the stuff from the lfs, and you know what? it's the exact same thing as filter floss.
 
Well that set up is completely different from your first post. That's all I had to go by at the time. When you say "micron pad" as you did it's only natural that I would think you were usings Rena's stock micron pad which definitely should be the final mechanical stage, unless of course you're using their SuperMicron pad, or a fine filter felt. The second description is indeed the correct way.

I see...meant the foam pads...sorry for the confusion
 
I see what your asking, the Rena "Foam Pads" are worth the investment IMO, you never have to replace them just squeeze them out every now and then I would not use floss in there place. I run big al's floss at the top of the filter to catch anything the foam pads leave.
I use these from rena http://www.petsmart.com/product/index.jsp?productId=2752394
I use big als floss in the place of this http://www.petsmart.com/product/index.jsp?productId=2752395&keepsr=0&clickid=prod_cs


I've used the foams since I got the xp3s. So then, the Big Al's floss is pretty much the same thing as the Rena Micro pads as far as "fine-ness"? How thick is the BA floss?
 
Floss is just a big bunch of fibers. I just grab a handful & pull it into the shape I want, trying to get the thickness fairly even. Quilt batting comes in a bed size roll 1/4-1/2 inch thick but isn't as dense as a purchased Rena pad. It flattens out some with water flow so I use a couple layers.
 
I've used the foams since I got the xp3s. So then, the Big Al's floss is pretty much the same thing as the Rena Micro pads as far as "fine-ness"? How thick is the BA floss?

The big al's floss is thicker than the rena floss
 
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