This thread is intended to show how I made a DIY HOB fuge by modifying an AquaClear 300 power filter. While the size of this filter will minimize effectiveness in larger aquariums, I believe it would be beneficial to smaller setups where space for a conventional fuge is limited. This could also be useful in providing a natural food source for livestock in an aquarium. At the time of this posting, I have added LS and a few small LR to the fuge, and I am now awaiting chaeto that I am hoping is crawling with pods, which I purchased from Dingo. I also will be purchasing a light in a day or so as well. The following are steps I took in making this DIY HOB power filter fuge In the photo below, you can see the components I have used... the Aqua Clear 300 power filter and two small pieces of eggcrate material. (One piece is not shown in this photo.) This is the filter media basket for the power filter. It normally holds the filter sponge and media cartridge. For this project, I used two sides of it, which were cut into individual pieces. This is the panel of the filter media basket I will be using first. It is used to separate the main water chamber from the chamber where the motor sits. I had to cut out two pieces of eggcratre material for this project. The first is being used to support the side panel of the media basket, and is 8 squares by 5 squares. LS will fill the cavities, but will not completely cover it. The second piece of eggcrate material will be used to keep the chaeto from leaving the chamber with the water flow, and is cut to 8 squares by 2 squares. Pods will be able to flow out of the chamber and into the tank. The smaller piece of eggcrate material is glued to the inside of the larger chamber at the spillway. I used Instant Crazy Glue for this, which is safe for aquarium use. Here you can see the position of both pieces of eggcrate as well as the media basket panel. After adding the LS and LR I hooked it to the back of the tank and started it. I noticed the water flow was blowing the sand all over the place. I turned off the filter to examine it, plugged it back in, and the motor didn't work. I disassembled it and realized sand got into the magnet of the motor causing it to stop. I cleaned it up and it was operational again. (Notice the sand blowing around the chamber.) When the water flows up the tube, it enters the chamber from the bottom, causing the sand to blow around. I decided to use the bottom piece of the media basket to try to reduce the water flow from blowing the sand around inside the chamber. I positioned it over the slot where the water enters the chamber. When I reassembled the fuge and tried it again, it did not appear to improve the problem. ( I was unable to show this in a photo.) CONCLUSION: At this point, I am uncertain what to do about the sand blowing around the chamber. It does not seem to cause any significant problems, and may cease as the fuge operates longer and the sand settles. The LS may become covered by the LS blowing around, but I am unsure if this will be an issue. On a positive note, these seems to be plenty of water flowing within the chamber to keep detritis from settling in that area. Updates will be posted as I keep track of the operation of this fuge, and also when I receive my chaeto. Comments and suggestions are appreciated.