I'll try to write the instructions, but if my camera was operational it would surely help. here's a list of supplies you need, some of which you may have around the house.
13 inches of PVC
1/2" inside diameter
4 90 degree PVC
1 T connector
1 open pore sponge about 4 1/2" by 3 1/2"
20 inces airline tubing
1 aqua fizz cylinder shaped airstone
It's about impossible for me to explain this. Cstricklin, I live in Cincinnati, Ohio, if you want to e-mail me I would be more than happy to make one and ship it to you via USPS, I have all the stuff to make them (except the airstone) It shouldn't cost me that much to ship it to you. All I ask is that you let me know how it works.
I check that everyday, sorry for the delay in my answer.