Yep. I used coke bottle sponge filters in my breeding tanks and they worked really well.
Coke / water bottle (20oz works well for 10g)
Uplift tube - I use a thin clear plastic tube made. They are generally made for sponge filters. I bought mine at my LFS
. Should fit very snugly inside bottle lip.
Gravel - Weight
1. Insert uplift tube into opening of bottle.
2. Cut the bottle in half at a smooth spot.
3. In bottom half cut as many slits with a utility blade as you can. The more the better
4. Add a few handfulls of gravel to the bottom
5. Add filter media to fill the top and bottom halves.
6. Slip the two halves together so that one is nesting inside the other.
7. Cut notch in uplift tube to hold airline tubing
I ran about 5 of these on different tanks and never really had a problem.