I would run the XP2 with a really good prefilter and some quilt batting (3-4 bucks for a giant roll at wally world) for mechanical inside. Then I would stuff it with eheim ehfi-whoobey whattey... Just the eheim bio stuff.
The ac110s I would run with 2 sponges and 1 bio each.
Now for my little (or large?) rant:
First of all, mixing species from completely different areas of the globe (all those fish mixed with the green sunfish) is never a good idea because of water quality differences.
Secondly, you have planned for wayyyyy too many fish in that tank.
1 oscar= 50 gallons
1 common plec= 60-75 gallons
6 Sds= commons would take up about 30 gallons, while redhooks would take about 60 gallons
1 green sunfish= i am not sure with this one
To keep your nitrates under 20ppm you will be doing about 3-4 80-100% water changes per week. If you get:
3 silver dollars - 20g
1 oscar - 50g
1 green sunfish - idk
1 bristlenose or other similarly sized pleco - 20 gallons
Then you could stick with 1 large (75-80%) wc and one smaller (50%) change per week to keep nitrates low when they are adults.
Do you want the pleco for the pleco, or for algae removal?