I ordered a SWC cone for my 180+65 system. I planned on running it externally, buy unfortunately the volute leaked. I now have a leak-free volute but the fear of another leak caused me to buy a bigger sump so I could run it internally.
There are a lot of opinions of course on skimmers, and after 6 months I basically came up with the following. Bubblekings are great skimmers but very expensive. The MSX line offers similar skimmate production and design at fraction of the price.
The new "hot" items are the cones. ATB used to lead that market but with the introduction of the SWC and Warner Marine cones, the ATB's seem ridiculously overpriced. I am extremely pleased with my SWC thus far. Build quality is outstanding and you don't get any better than the askoll pump (sicce options available too).
The Orca 250 is a very well-regarded external skimmer. Unfortunately it uses a lot of power and there are many reports of collection cup overflow.
In the end I wasn't convinced that external skimmers were worth the extra money or were any more effective than some of the others, and I sleep better knowing any leaks are contained by the sump. Still, if you don't have the room, you may have no choice.
