welp..
the tunze 9010 is actually a decent skimmer for it's size, and it does work pretty well on smaller systems that dont have room in the sump for other skimmers, but i'd say it's efficency max'es out at about 55g...they give it something like a 250g rating for low bioload...lol
and it's expensive at over $360 retail...
a word about vertex skimmers...
I dislike them strongly...
the reason being the evil resun pump they use on it.
it's just a euro-reef knock off with a poorly designed bubble plate and a janky pump on it... another honya shenizen made skimmer with little thought for the consumer...
SWC skimmers are made in china as well, but the quality is much better, thicker acrylic and pvc, and the pumps they use consume less power and have performed very well on other skimmers for years, so there's no guessing if your getting a good pump or not, which is the heart of the skimmer, and makes or breaks it IMO...
the 160 cone would be great for your tank, but if you wanted to do SPS, a high bioload, or upgrade to a larger system, then you might want to take advantage of the sale on SWC mini s skimmers with sicce pump,
the 160 cone gets 700lph air injection for 25 watts, and costs $275 at most places,
the mini s cone gets 1200lph air injection for 25 watts and is on sale for $279 at a few places
the mini s would be good for up to 200g, and work great on your 75g.