Hi everybody. I'm new here.

I have 2 female and 1 male ADF (not clawed). They currently are housed in a 6 gallon Fluval Edge tank. I would like to switch them over to a 20 gallon long
and MIGHT end up adding a couple of guppies later. I keep the tank right above my bed. I am in search for a better filter. I have asked numerous pet store employees and always get a different answer (both from big chain and non-chain stores).

I am not happy with the Edge filter that is attached to the hood, in the middle of the tank. It's a pipe filter that you can set at different flow levels. There is about an inch empty from the top for the frogs to grab air. If I have it at the highest setting the flow out pour is nice and quiet like in a waterfall
style but the current is way too strong for the frogs to swim through. If I have it on the lowest setting the water trickles in and is too loud for me and I
don't think the frogs like it. Plus the motor itself hums a little too loud for my taste.

So it looks like a few options. The Marineland Penguin BioWheel people seem to like but I had one guy say the wheel can be a little loud. There is also the
underwater Fluval filter that you can direct where the flow goes. The guy said that the underwater current shouldn't be a problem for the frogs and that it shouldn't make any noise. There is a small sponge in the filter but no cabon or anything else so I was worried how effective this would be, not that the frogs need much filtering. Then there is the Whisperer type. This is supposed to be the most quiet. I am wondering if I go with this do I use a pipe intake or submerged filter? Will the current be too strong? I've seen people talking about the Aqua Clear brand but don't know much about it.

And one last point to make, I plan to do 2/3 sand substrate and 1/3 gravel. I
had one guy say that the submerged filter should be okay if I keep it on the gravel side while another lady said if I use any sand it would ruin the motor, which I have heard.

So any suggestions? My main concerns are quiet and a low to mild current. Sorry for the long post. Thanks.