i have that filter, and also have 2 fluval 3 plus filters. I place the output near the surface so it ripples the water, but not so high that there is a waterfall effect (too noisy!)
It's best to ripple the water as this helps oxygenate the water. However if you have an air bubble stick this will also help oxygenate the water and in this case you can put the output from the filter below the surface of that's what you want.
(ps, i also like to have the output rippling the water as i could easily see if the filter were to stop working!!)
QUOTE(sandy @ Aug 25 2006, 03:19 AM) [snapback]566375[/snapback]
Is it new? If so you should have attachments to go into the top of it which draws air down and into the outtake.
The actual nozzle itself should be just under the water with the attachment above water and you lift the filter to where you want it so you can have lots of bubbles or less bubbles. You can also alter the flow of air by turning the black attachment on top.
If you dont have any attachments then as long as the top of the filter is just breaking the surface that is the highest point out the water you should really have the filter.
oh yeah, i forgot about the little air intake bit at the top!! i dont use that anymore as it makes a strange noise i think. and i prefer to simply have it rippling the top of that water. it looks quite nice too!