Fillter Medium

[widgetuk]

I have just inerited a fluval 404 external fillter it as a sponge alfa grog and ceramic rings i took them out to clean and forgot what goes first the rings or alfagrog
any one have a spare brain cell

 

[squishy_1984]

in my 105 i have carbon at the bottom, polywool in the middle and bio max (rough rings) at the top.