I love my filter...
Actually, I have used a few low profile filters. The one I use now, and have used the longest, is called "DUETTO" (DJ 50 MODEL). Basically it is a lowprofile pump with a filter chamber. This pump has two filter stages. I don't like the medium setup... and it also has a Charcoal canister and flow regulator. The pump is completely submersable and has two nozel attachments, hose attachment, or flat aimable jet spray. It only needs to be 1/2 inch below the water surface, I have had mine running at the water surface for a while, my newt likes to burrow under it and push it up.
NOTE: Cut the glue points on the charcoal canister and fill it with charcoal/ammo mix... this will cut down on odor, and excess amonia nitrate pollution (Decaying frog poop).
I run this filter for one hour, 5 times a day. (My frogs and tiger salamander like the quiet time.) This will do several things...
1). Extend the life of the pump.
2). Allow benificial bacteria to work better.
3). Stops your SMALL water area from over-heating from pump operation.
4). Stops the filter from clogging quickly, which stops waterflow... adding more heat.
5). Keeps your water crystal clear.
As an added bonus you can add some "Glass Shrimp" and some floating lettuce plants, (Not lettuce, it is a nickname of a floating plant.) Frogs love to sit on this plant like it is a lilli-pad. This will also provide cover for the glass shrimp. The shrimp will clean the plants and most edible debris, and the plants will absorb a lot of the toxic chemicals and gasses in the water.
I do a 1/2 water change every month, and I add about one to two cups a week to the water. My water area is a plastic sink basin with the rounded edge cut off. The container is surrounded by coco-fiber bedding and stones with large flat mica-stones around teh edges. The pump rests flat on the bottom, under one of the larger stones that hangs over the water tub.
NOTE: Rest the pump flat on the bottom, with the nozzel pointing directly up, not to the side... This thing will create an unwanted flow that will keep your pets out of the water. Even with the flow at 1/3 you will see a whirpool start to form... and fish running out of breath... um... water...
FYI: I have a 30 gallon tank with 1/3 water (Basin) with two Chinese Alge Eaters, one Fire Belly Newt, three Fire Belly Toads, one Grey Tiger Salamander, four Glass Shrimp, and several plants.
The plants are as follows, one Clump Moss, two Blanket Mosses, one Swamp Moss, two Stunted Ferns, one Common Swamp Lilly, three Creeping Swamp Vines, and six Unidentified Swamp Plants.
I think I need a bigger box...
P.S. Don't use the AIR LINE thing... this will render the pump useless unless you stand it up to operate. The air will build up inside, and stop the impeller from functioning, which will burn up your pump.