nwaas.com

I've finally run out of foam used in my sponge filters. Today, I got samples of several different foam types to see what might work as a replacement. Most important is to verify that they aren't toxic to fish. I made foam blocks to test for toxicity. I've got one running in a tank with a test fish. Another is the same material, but a lot softer. I'm assuming there is more air in that type, but I've run into a problem cutting the hole. Finally, I wet it, and put it in the freezer. Later tonight I'll take it out to see if I can cut the hole in the frozen material. This will be pretty good if it doesn't kill the fish, and can be worked into the shape I need. Denny

Well, after 3 hours, the fish is still alive and the frozen sponge was able to be drilled (although it was a little rougher than the other cuts). Denny

I am wondering what you've come up with for a new sponge. I am planning to add sponges to all of our tanks but I want to tailor them to fit. I can't seem to find a large sheet/square of the black open cell foam anywhere.

It's not the black foam, but I did get some from Oklahoma Upholstery Supply in Tulsa. It looked to me that the HR foam worked best. Ideally I would have preferred a little larger pore size, but it works just fine. Also no additives that can kill the fish. Denny www.FabricsbyOUS.com