When i decided to order some fish from Raingarden, I bought a dollar/gallon 40B from Pet co and decided to set up a pond-type filter system for this aquarium for the larger two fish. I put three of my HOB filters on the 30 gallon I used for the smaller two fish.
Here's how I set up the 40B.
For my filter container, I selected a Rubbermaid wastebasket. This one is about 6 gallons total capacity. In use, it will hold about 5 gallons. The rule of thumb for pond filters is that they should have10% of the pond volume. Since my "pond" is 40 gallons, my container is a good size.
My fish tanks are in a spare room. If I had them in the livingroom, I would select an attractive flowerpot for the filter container, maybe something like this: http://www.lowes.com...ollow&cId=PDIO1
I put in an outflow spout, using a piece of 1" PVC pipe through a uniseal. http://www.aquaticec...s/1617/Uniseals
You see this on the left here:
The uniseal is black. The pvc pipe is white. A uniseal is by far the easiest way to put a pipe through the wall of a container. One simply drills a hole of the specified size, pushes the uniseal into the hole, and pushes the pipe into the uniseal. Around the base of the wastebasket is the tubing that will deliver the water from the pump inside the tank to the filter. I used 1/2 inch tubing, which you can get in the pond department at HD or Lowes. The pump is on the right, and all the out-of-focus black stuff around it is the nice long power cord.
The pump is an earlier version of this one: http://www.harborfre...pump-68395.html These pumps are less than half the cost of comparable items at HD/Lowes, and have a very good reputation among ponders.
The white contraption to the right of the wastebasket is the plumbing that conducts the water from the hose to the bottom of the filter. The dark gray piece at the top left is a 1/2 inch barb fitting http://www.lowes.com...%7C0&facetInfo= . The hose will be pushed onto the barb and held in place with a clamp: http://www.homedepot...p&storeId=10051
The lighter gray piece on its right is an adapter. The left end screws onto the barb fitting, and a 3/4 inch pvc pipe fits into the right end. Then you see a piece of 3/4 inch pvc pipe (with some red letters on it) going into a T-fitting: http://www.homedepot...1&storeId=10051.
A vertical pipe goes from the T-fitting at the top to another T-fitting at the bottom. At each end of the T at the bottom, I push in a short piece of pipe and put an elbow fitting http://www.homedepot...1&storeId=10051 on the pipe. It looks like this:
This bottom T and elbows is called a "swirler," since when the water comes down the pipe and out through the elbows, it swirls around the bottom of the filter. This swirling action helps to sediment particles in the water at the bottom of the filter. In all honesty, I'm not going to get much of a swirl in this container, but swirlers are fun to make.
All I really have to do at this point is fill the filter container with media, but I like to have a bottom support for the media, and above the media, a support for plants. The support I chose in this case is the rigid filter pad called matala: http://www.drsfoster...99&pcatid=15799 .
I cut two pieces, one that will fit tightly a couple of inches above the swirler, and another that will fit tightly just below the out spout.
I put a hole in the center for the vertical pipe. You can't see it in the picture, but I slit each piece of matala from the center hole to a side so I could put it in and take it off without pulling the plumbing apart.
The bottom pad:
A bag of media:
This bag has a lot of frayed plastic rope as media. II got some cheap rope http://www.harborfre...rope-90760.html cut it into about 18" lengths, fused one end with a flame, and unwound the rest. Lots of surface area, and lots of work. I also threw in some pieces of plastic junk, some nylon mesh "bath sponges" from the dollar store, and the scraps left from cutting the matala. Later I added some of my current favorite commercial media, pvc ribbon. The filter is sitting in place and you can see a corner of the tank with Adam and Eve wondering what I'm doing and when I will get my act together and feed them. You also get a great view of the toes of my shoes, LOL.
Then I put in the top matala pad:
Adam is watching me very carefully.
Now all I have to do is put the pump in the water and connect the pump to the filter with the hose.
One end of the hose goes on the barb at the filter, and the other goes on the pipe at the top of the pump. One should put clamps on the hoses, but I didn't. They fit on nice and snug.
Here's the pump end. There are suction cups on the bottom of the pump.
Adam and Eve have to get in the picture.
I put some plants (in pots of gravel) in the top of the filter:
I also moved the pump from the bottom to the side of the tank with the inlet side pointed to the bottom. When it sat on the bottom, debris accumulated under the pump. Adam and Eve look quite pleased.