So after reading this article & thread https://www.turbosaquatics.com/threads/coral-feeding-an-overview-by-tim-wijgerde-ph-d.270/ http://www.advancedaquarist.com/2013/12/aafeature I had a few thoughts so share on the realm of public opinion. One focused-upon issue with the enclosed waterfall algae scrubber (like the ones I make) is bubble removal. The article in the above link mentions use of aeration when not using a skimmer. Of course the UAS does incorporate this, but the bubbles "needed" for a UAS are large and are purported to be for water motion, random algae movements, etc - not microbubbles similar to what is used for a skimmer, which is what should be "replaced" when one makes the decision to go skimmerless, for whatever reason. One method is to turn your skimmer way down so that you are really not skimming, but just spinning bubbles around. This means $ spent on power to do nothing as far as what the unit (skimmer) was designed for, but means you can use a joe blow skimmer if you wanted to. Another method is to place some kind of "catch" device under the scrubber drain to allow for the effluent to churn out bubbles naturally, but then allow them to diffuse out or be trapped out in similar fashion to how a skimmer does this. One could also force bubbles into the equation by adding an airstone, one of those wood-based ones that produces the super-fine microbubbles. This might be pushed even further by making a recirculating scrubber system, where a unit is driven by a dedicated pump and the water is pumped out of the drain reservoir back into the scrubber unit, and there is a controlled input and output of system (tank) water. Then, then only microbubble removal that would be needed would be on the final output, and if that was slow-motion water, if could be easily trapped out by up/downs. Thoughts?