Sponge Filters
I would like to share with you how I make sponge filters.
- Purchase a large piece of open cell foam. You can purchase these at fabric and hobby
stores.
- Use a very sharp knife and cut the foam into the appropriate size blocks for your tanks.
Cutting is easiest with a long sharp knife cutting in one direction without applying a lot
of pressure. Going back and forth or applying strong pressure catches the foam and tears
it.
- Individually place a block into a sealing plastic container, top down. Fill the
container with water and make sure you get all the air out of the foam. Put the lid on the
container and place it in the freezer. A container as close to the size of the foam block
works best.
- Once frozen, remove the block from the freezer and immediately drill a hole into the top
with a wood drill that is slightly smaller than the tubing you choose to use.
This process is very easy and works great. To reiterate the 2 most important points:
- Make sure the foam is covered w/ water when it freezes or you will not be able to drill
into the foam.
- Make sure you only take 1 foam block out of the freezer at a time and drill immediately
or the foam will defrost, catch on the drill and pull the foam instead of cutting it.
I think you'll find this to be an easy cheap method to make sponge filters.