Yes and yes

I've used the BakPak IIR on 20-ish gallon systems and it is a joy. They are just as good (but easier to clean/maintain) as the Aqua-C Remora. As with any
skimmer, you need to keep them clean (both the
skimmer throat and the pump) and tuned properly.
Ensure that you are using the proper rated
skimmer for your system. Keep in mind TOTAL water volume of your system, not just that of the display. Also, for any
skimmer that says it's rated for 100 gallons, I've found that means 50-75. One rated for 200 gallons, I'd use for a 120 gallon...etc. understand?
Ciao for now.
Dave