was thinking of throwing them into the fx5 instead of having the fluval bio max....
anyone no of them? or no of best media to throw into fx5?
i just feel the bio max i have in there right now isnt that great maybe im wrong!!

with all media you get what you pay for. you could just get away with sponge or pot scrubbers and anything in between. but when it comes down to how much bactiria can live in the space your provided, a good quality media will win hands down. some media allow bacteria to form deep inside the balls/tubes. sometimes this will even be anaerobic bacteria that remove nitrate. Etheim and fluval make good quality. they will all give a guild to how much area the bacteria have to grow. but typical of competing companies is they use different measuring methods just to confuse us. shame. fluval bio max and Etheim pro offer some of the best. I am sure marineland are reasonable too. look at the surface area and compare. Etheim pro substrate offer 450m2 per litre surface area. this is very good. what ever you buy bag it in a fine net bag or stocking socks to prevent it getting washed into the impeller when it breaks up into small parts.

any bioballs or ceramic rings will work just as fine. what matters is the lateral
surface area where bacteria will live and do their job. the more surface area,
the better. but as marcus had said, be careful in putting a bagful of bioballs,
it it got into the impeller, its either break into small pieces or break the
impeller of your pumps....

I have HOB filters however I grabbed about 8 mesh bags and I found I could stuff a whole bunch more fluval ceramic rings into those and fit them into the same space. I use several different sizes of ceramic rings as well.
I have 4 mechanical filters with 4 bio wheels and about 8 bags of ceramic rings now and they work very well so far. My personal experience is that ceramic rings have more surface area for bacteria. JMO. The balls I couldn't fit as many...not even close.

aren't the marineland bio-balls the plastic orbs you fill with various media? perhaps I'm confused and am thinking of something else. It's the orbs that you fill; I think these are traditionally used for sump filters.

I think everyone else has you covered already!

a mesh bag or or net that contain bioballs prevent the bioballs to get inside
the pump chamber that can break the impeller.
some bioballs look like this

thanks Paul - i was indeed confused. I was thinking of something more like this:

www.fosterandsmithaquatics.com/product/p...742&pcatid=12742

I just love this site - i learn something new daily!

basically, when you did not open the whole sphere, that is also a bioballs
but it contain granulated particles inside to provide more lateral surface
for the bacteria. that principle is similar to the substrate of pebbles.
however, in the filter, the flowing water make bacteria more efficient
doing their job.