Im setting up another fish tank 35g. The hood is an Eclipse with built in filter. I went to the fish store and bought the filter cartridge but they didnt have the BioWheel for it. They ordered it for me and it will come in a week. Can I setup the tank and start to cycle it without the BioWheel?
yes it will cycle. The nitrifying bacteria grow everywhere, on the glass, gravel, in the filter on decorations etc. Of course more bacteria will grow on an area with more surface area than a flat space ie the glass.
The filter cartridges actually do hold quite a bit. You don't even need the bio-wheels for the filter to work. Just don't toss both cartridges at once, and if you only have one, consider a second filter. You want want to discard your cycle. Bacteria does grow everywhere, but its the water flowing past that carries what they eat, so a whole lot more can live where the water is moving most, like in the filter, without going hungry.