Eheim canaster filter 2217 questions?

[AC2020x]

Hey, I got this filter off of craigslist along with my tank. I decided to clean it out obviously and i have a few questions. I'm unsure of how the whole thing goes together though. I know there are two green perforated plates with legs one on top and one of bottom. This is my understanding of things from the bottom to top with reguards to how it was set-up when I got it.

Bottom- gree perforated plate with legs down-
2 Blue filter pads- on top of that all of the filter media- including carbon/little plastic spheres and cylinder things. (IDK should these go in any specific order?)
Next up was a small thin black filter pad-
then on top of that the other perforated plate with legs facing up.

then just put the cap on.

Through the manuals and stuff I looked though i didn't see any plastic spere things so here is a pic of them with the cylinder things.

PS: this is my first canaster filter so i don't really know what i'm doing!

Thanks alot for any help
-AC

[toddnbecka]

Looks like fluval ceramic biomedia and some sort of plastic spheres I'm not familiar with. You may as well clean out the carbon and toss it. My Eheim has something similar to the ceramic fluval media (except they're thinner-walled with larger openings through the center) in the bottom basket with the coarse blue pad on top of them. The upper basket contains Eheim media (balls of some sort) with a fine filter pad on top of it. A prefilter sponge will help slow down the process of clogging the media with debris, but when you notice the flow rate diminish you need to clean the media. Eheim canisters are mainly designed for biological, not mechanical, filtration.