I am currently designing my filtration system for a 220 gallon tank. I see a lot of sumps in the hobby but I was recently at a fish store in Oahu where they had all of their filtration in-line, external of a sumps and I really loved the feel of it. I'm considering having my outflow come down and flow through all my filtration like turf scrubber and skimmer in-line. Each component of my filtration having a bypass so I can individually control flow through parts of it or completely isolate them.
I was wondering what the pros and cons of running your filtration outside of a sump. The one major benefit of the sump that occurs to me is that it adds water volume to your system.
I'm not sure what you mean by in-line?
Like one of Lifeguard's systems?
Modular System Packs
Complete pre-assembled Modular Systems ready to go in two configurations.
Reefpack 500
For fresh or salt water Aquariums up to 100 gallons.
FEATURES
In-Line System R440450
Compact System R440455
Both Versions include:
- Quiet One 4000 Pump (1022 GPH)
- AF 94 Mechanical Filter, AF 93 Chemical Filter, AF 92 Heater Module, QL 15 UV Sterilizer
- Complete Customflo Water System Kit. Assemble parts in multiple ways to create desired flow patterns
- Union Shut Off Valves
I'm not sure how you'll run a skimmer without a sump to return the water to the tank – skimmer's aren't pressurized by their nature, so water will have no way to get up to the tank.
AquaC has made Remora hang-on skimmers that were the right size for this tank, so I'd investigate one of those.
I think I'd also consider a Tunze
Comline® DOC Skimmer 9012 DC + one or more
Comline® Multifilter 3168's or
Comline® Streamfilter 3163's for media filtration and equipment hiding and an
Osmolator® for ATO. (One unit can hide your ATO sensors, the other can hide a small heater, which actually boosts the heaters effective rating.) That gives you an in-tank setup: Skimmer, filter and ATO, which all fit into as few as two magnetically-fit in-tank modules. If you wanted, you can expand the system with more modules, inlcuding a second filter module, a wave box, etc.
That's basically setting up a super-sized
Reefpack 500 with that lineup if you wanna compare with that for the idea.

Reefpack 500
Comline® DOC Skimmer 9012: Designed for mixed aquariums or soft coral aquariums with 200 to 1,200 ...
mehr
0500.000
608.40 USD
The 500 is only rated up to around 150 gallons for a heavily stocked system. Upgrade the package to the DC version of the 9012 skimmer and it should be great for a 220 gallon system.