No it's a superb skimmer I'm setting up a separate system for growing out frags and backups of my current corals putting the 170 on that... Sooo I always wanted to try a Deltec seeing so many European reefs running them.. But At this price point I think it's time ...HI there,
The neck diameter on the 1456/56 is 3.5 inches. The beauty of the newer line of Deltec's is how impressively compact they are. Especially compared to similarly classed skimmers. I have learned myself that bigger does not always mean better, and when proper attention to certain metrics like pump size and needle wheel size and pin count & length, and air and water through the skimmer, and neck/body diameter can make all the difference in stability and over all performance. As opposed to actual size and simply blasting as much air as possible into the skimmer. Sorry for the mouthful here, but this is an area where Deltec truly shines and you almost have to see one in action to really believe it.
Will the 1455 out skim the 170? I'd like to think so, but can't say so for sure. However, it will be a near perfect fit on your 180, and you can expect constant and steady dry foam, and very little "tweaking" . Oddly enough this is one of the rarer instances where ether Deltec is actually they cheaper one at 499.00 vs 859.00 lol! If you wan to put the Vertex up against the comparatively priced 1660 well, then Id' say the Deltec would come out on top but it would still be a bit oversized on your 180.
curious though, is there anything you not happy about with the vertex?