eheim cannisters are incredibly quiet. And if you place the output tube below the water line, it's definitely a quiet set up.

I can't help you on your filter set up problem - I've never done a UGF set up.

As you really can't keep live plants in with Goldies, I would caution you not to use a UG with them at all.

With all my fancy, exotic tropicals, I'll admit that my pet fish are a pair of fat, useless mongrel Shubunkins so tame, they will eat from my hand and allow me to gently lift them up in the water.

But just 2 of them as still only sub-adult in size, will also foul a tank faster than 200 guppies.

To keep them clean, I use pebble sized "gravel" too large to get caught in the siphon hose.

It covers the bottom and looks nice, but water changes with the assurance of nothing trapped below a deadly plastc plate, waiting to poison them, is pretty easy.

Whatever else you do with Goldies, double or even triple the advertised filtration capacity for the tank size and water change down to their dorsals as often as you can.

As cold water fish, Goldies require a lot of oxigen, so the easiest for them and you, would be as already suggested, a cannister filter.

Then, you could discharge back into the tank though a spray bar and greatly increase oxigenation.

Give them optimum conditions and pet carp will live a long time and give you pleasure every time you look at them.

Poor Goldies! So common and cheap they get little respect, so too many people don't apprecite what great tank pets they can be.

Yes the powerhead intake sits on the lift tube. Unless there is an adapter to make it reverse flow or the pump is reversable. I would scrap the UGF/RUGF also. Put a sponge over the intake of the pump/powerhead and use it for a secondary filter or polishing filter.

UG's are a good biological filter but have to be siphon cleaned often.

James:

Yes, but for planted tanks only and we are talking Goldies here.