Just wondering what I can do to this external filter in the way of improving biological filtration. Not sure this filter is really big enough for the 218L tank it's used on, but it's all I've got at the moment. Think it's rated at 1000 lph, also have a koralia 2 running when co2 comes on.
In the bottom tray I've got some sort of alpha grog stuff, in the top tray there's a piece of foam that half fills the tray.
So do I need to keep the empty space at the bottom? It seems I've got very little media for the volume of the filter itself. I was thinking of putting ceramic rings under the foam in the top tray, are ceramic rings better than alpha grog, if so I might replace the grog.
TIA
In the bottom tray I've got some sort of alpha grog stuff, in the top tray there's a piece of foam that half fills the tray.
So do I need to keep the empty space at the bottom? It seems I've got very little media for the volume of the filter itself. I was thinking of putting ceramic rings under the foam in the top tray, are ceramic rings better than alpha grog, if so I might replace the grog.
TIA