"Recharging" the Holding Tank Vent Filter

By Charlie Billings — Nobska, 32-057, Bremerton, WA

Step 1 – Purchase a SeaLand “Sani-guard” 5/8-3/4” holding tank vent filter (Mfg # MSD 309310001) from West Marine or other marine supply store.   Install in-line with the holding tank vent hose making sure that the filter is mounted above the vent hose exit from the holding tank.   Use for one season.

Step 2 – At the end of the season, or whenever you desire or need to change the filter, remove it from your tug.   Remove the label on the main tube (body) of the filter.   With a hack saw, band saw, cross-cut hand saw, cut the tube approximately 1½ ” in from the end cap of the filter.   (Photo 1 & 2)

Step 3 – Empty the contents of the filter into your trash or other responsible place (it’s just smelly “activated charcoal”).   Clean the filter tube and the two pieces of foam within the tube with soapy water and let dry.   Save the two pieces of foam from within the filter housing for later use.

Step 4 – At your local hardware or DIY home center, purchase a male and a female junction that fits the outside diameter of the filter tube.   If you don’t have it already, purchase a can of PVC primer (regular acetone will suffice) and a can of PVC glue.   Glue the male and female fittings to the cut ends of the tube.  (Photo 3)   Insert the clean foam pieces into the ends of the two pieces of the filter housing.

Step 5 – At your local pet store, purchase a bag of “activated charcoal” used for fish aquarium filters.   Fill the long section of tube with the “activated charcoal”.   Screw the short section onto the long section and replace the filter in the vent hose on your tug.  (Photo 4)   You should have enough “activated charcoal” to last a couple of seasons.

Step 6 – When you feel it’s time to replace the filter, just remove, take apart, dump the old charcoal out and replace it with new activated charcoal”, thus saving from having to purchase another entire filter.

Photo 1	Photo 2
Photo 3	Photo 4