That looks like a good idea, but I'd have a few concerns.
1. Cleaning - does the gunk all fall out the bottom when you remove that thing from the tank to clean it?
2. Appearance - You'd need to hide that thing pretty well so it doesn't look like you're going for the "polluted river" look, complete with authentic discarded soda bottle.
3. Efficiency - Is that powerhead really strong enough to pull water through all of that media?
4. Design - Will the media fall out the bottom of the bottle once laded with goop? Will the bottle fall off of the powerhead due to the "press fit" connection not being tight enough?
Last edited by kingdave; 08-14-2013 at 08:44 PM.
Reason: misspelled word