skimming question..........

my setup is an old reef octopus skimmer in a 30 gal sump/fuge for a 55 gallon tank.. as of now i am skimming very dry, it takes around 2 weeks before i have to empty the collection cup.
is that too dry? i was told to skim a bit more wet.

next... when cleaning the collection cup i just dump it and clean the cup and lid, but not the center chamber cause i dont want to wait for the build up to happen before the skimming starts. is that ok??

That should be fine, your tank still needs to re cycle itself, seeing you just sold me your old tank and got that new one.
This is why your getting brown algae, as its one of the first stages of algae you will go through. Just be sure when you see red algae you get some stuff to take care of that.
I have the same issue, hense im looking to upgrade to a bigger skimmer.