Filter output

[Tl52505]

I just purchased and setup a fluval 207 for my 37 gal tank, and following a video I got it setup but noticed the output was above the water in the video which created a lot of splashes on the top of the water and was very loud. I figured this was for aeration but am not sure if it would affect how the filter works if it was under the water. I have a 40 gal bubbler in the tank so aeration should not be a problem. Would it be ok to put the output under the water or slightly under the water

 

[Lajos_Detari]

The output position won't affect the filtration.
You can put at any position that you like.
But usually I like to add more aeration by putting it slightly above the water surface.

However, if you find it too strong for your fish, you can always lower it down.
Some fish don't like strong current but some fish are ok with strong current.
So, it also depend on your fish.