Join Date: Nov 2004
Location: PA/MD/DE tristate area
I'm fixin' to make a unit from a water filter housing (ebay), inline pump, and some fittings/valves/quick disconnects etc. I like the water filter housing because I know it won't leak, it has an air escape button to purge bubbles, is rated for way more PSI than it will have running through it, takes standard NPT fittings, etc. The pump will go on the out side off the water filter housing. Just bought a rubber bulb siphon pump from harbor freight which will go on a Y branch of the in line, to start the siphon, then that branch of the Y will be shut off via valve. Filter cartridges are easily made using the inner tube of a commercially available paper-accordian style one and making a sleeve of filter foam. I might even opt just to use coarse commercial ones. My application isn't a canister filter, but rather a targeted mulm vacuum cleaner though (think: gravel vacuuming using a python but with a return to the tank of the water). But you could fill around the filter cartridge with bio-matrix or do inline housings with different fillings - one with a filter cartridge to catch debris, one with biomatrix. I like to buy the clear housings so I can see what's going on in there, too.
It's probably not cheaper or more space efficient than buying a good canister, but I can have a much more powerful vacuum cleaner this way, and switch out the dirty gunk and filter cartridges much more easily than opening up a standard canister. With a standard canister, you have to remove the entire filter to a sink, clean it out, then re-set it. With the water filter housings, you turn off the water using valves on either side of the housing, unscrew the bottom, clean that out. Inline pump is on quick disconnects either side for quick maintenance.