My girlfriend and I were at the Ikea store a few days ago and they had a 10" window squeegee for $2. Its just a hollow plastic handle that looks like it mounts onto a broom handle(you could glue pvc to it to make a longer handle if you need) and then its a silicone squeegee mounted to the plastic with aluminum, so no rust. I gave it a whirl in my tank when i got home and it took everything right off the glass except for a small spot of coraline algae.