Placement of filter and heater

I'm a bit confused how to place my filter and heater in relation to the water level.

I have an interpet pf2 which I have protruding about an inch so the water comes out and breaks up the surface. But it's quite noisy.

And I have an interpet heater on the back of the tank again the top protrudes about an inch over the water line.

I've seen some filters and heaters totally submerged, should mine be?

That filter can be underwater further than it is, for sure. There is a small venturi opening in the top and when I used the pf4 in a quarantine tank I had the water level so that was the only part poking out. That will significantly reduce the water noise but you will still hear a mild hum from the unit.

As for the heater, they can be used completely submerged. Just be sure that they are not resting on the substrate.

Thank you, I do have to top up the water a little and do a water change so I'll adjust it all, see what happens?

I’d move the filter down so it’s parallel with the water line so you still get water movement but without the noise , I like to keep my heater halfway down the tank mainly so when I do a 50% water change it’s still submerged