This is probably a silly question but can someone explain exactly how / what bio balls work / do ???? dummy

bio balls are supposed to provide a medium for beneficial bacteria to grow on.

Ok thanks. I take it do not clean just leave to grow? :huh:

i have never used them but i think your assumption is correct, you don't wash them.:)

bio balls work on the same premise as alpha grog, they provide a loarge surface area with which water can flow effectively and circulate oxygen and nitrates etc to the beneficial bacteria.

A complete and utter waste of money IMO as alpha grog is better and long term more tank friendly and better looking, also the producers make it out to be a miracle substance, when in all reality it is nothing different to what i would put in a BB for target practice

What is alpha grog? :huh:

its used as a filter media, more typical in ponds and sump tanks but can be used in tanks as its is hard and alkalii based it shouldnt really be used in your average tetra tank

Ahhhh...kinda looks like tufa...is it synthetic or natural?

sounds like some kind of porous limestone....

Hit the nail on the head seedy, :) i dont know what tufa is so i cant help ya there dude, but you were right on the limestone bit