Would anyone like to make your own canister filter? Go to Walmart, and buy a lock lock plastic container. Find a small submersable pump to put in it. You might have one laying around the house, like I did. Get some plastic tubing as large as will fit into the back holes on your tank if you have them. I bought 7/8 clear plastic tubing. One is longer, the out take tube, and goes around the back of my tank, and into the right hand side hole. The other, is shorter, and goes into the left hand side hole. The filter sits to the left hand side of my tank, in a basket. You will need to get a small piece of clear plastic tubing, that will fit onto the end of your pump, the out nozzle, and the outside of it, should fit inside the 7/8 tubing to go out of the filter. Super glue this small piece of tubing, inside the larger tubing, and onto the end of the pump. You will need to cut three holes in the lid of your lock lock box. Two the same size as the 7/8 tubing, and one the size of your power cord. Cut the end of your cord off, and buy a replacement plug, and put on the cord, after feeding it through the lid. I bought four white plastic washers at the hard ware store, that were 7/8 inside diameter, and superglued these, one inside the lid, and the other outside the lid, for each tube, for stability. Place the tubes through, and super glue! LOTS of Superglue! 
The gel works best! After all glue is dry, I placed water and live rock into the bottom of the filter, and used the plastic mesh you get at craft stores, to make layers to put filter media into, above the live rock. I have one piece of charcoal media, and one piece of fine filter media cut to fit. I also cut a small hole for the intake tube to go down the side, into the bottom of the filter, so that it will keep the bottom fresh too. The pump is placed on top of everything, and it pulls the water up through, and back into the main tank. It works really well. You will need to keep the filter media clean, but it is easy to open and close, with the lock lock lid!
The gel works best! After all glue is dry, I placed water and live rock into the bottom of the filter, and used the plastic mesh you get at craft stores, to make layers to put filter media into, above the live rock. I have one piece of charcoal media, and one piece of fine filter media cut to fit. I also cut a small hole for the intake tube to go down the side, into the bottom of the filter, so that it will keep the bottom fresh too. The pump is placed on top of everything, and it pulls the water up through, and back into the main tank. It works really well. You will need to keep the filter media clean, but it is easy to open and close, with the lock lock lid!
