Man, this sounds like my tank! An emperor 400 sure does the trick on a little 10 gallon, doesn't it? As for the skimmer, don't even worry about it. With a little waterchanging the skimmer's purpose is eliminated. I went a step further than you and forced a penguin mini on there for even extra filtration. All this filtration makes it able for me to house a peppermint shrimp, a nean damsel, a green clown goby, and soon an engineer goby. So far, I have lost nothing due to ammonia or nitrates, but if you want to play it safe on the fish, then go for it.