I'm currently using an eshopps skimmer for my nuvo 20. It's in my left second chamber held by a magnet. The cup fill up with a really dark skimmate after 2-3 days. Granted my first skimmer but, I would highly recommend it. The only downside to the skimmer is microbubbles everytime you restart it. It does go away after and hour or two. Besides that, maybe a little collection cup.