A
Antipofish
Guest
Calzone said:I know this is true, because if you feed a filter with 12mm hose and output with 16mm hose, you must surely have less flow than if both hoses were 16mm. Ultimately this is because the circulation around the "closed" loop is all drive by the pump, without it there would be no flow. Now, I would suggest that if you were feeding the water in through the media from a different tank say by gravity, things might be different. And actually pumps are crap at sucking and good at pushing, so I can even imagine that friction through the media has more impact than friction in the outlet (depending on pump design).
One wonders therefore why eheim suggest you fill the filter rammed full of media as this will reduce flow a lot and isn't necessary (apart from the obvious reason that they sell more media that way).
We should do an experiment on this and sticky it. Debunk the myths.
The thing is, nowadays most Eheims come with media. And the joke of selling loose media is, I know of a retailer who stocks Eheim filters cos he reckons they are the bees knees, but WONT stock their loose media, in preference to Sera.
Im now thinking along the lines of (in my 2075 or 2078 if i get it) a layer of Eheim Mech Pro (or anything similar), a layer of foam for anything the Mech pro has missedm and two layers of Sera Siporax. And now Im thinking of the siporax not necessarily for its "claimed" biological benefit (although I still subscribe to that but for slightly different reasons) but because it is relatively open and will not affect flow as much as Eheim Substrat Pro for example.