I run both skimmer and Drop 1.4 and like the skimmer better.... it is pretty hard to clean out the DROP because it has these strings inside that the algae really sticks to. BTW, if you ever need to really clean it out, use a pressure washer... works great, but you have to take the entire thing out, wires and all. My skimmer is a really old one that it really easy to clean. I saw someone say that skimming is not good for the filter feeders, but I don't have any issues because I dose a ton of Pyto all day (currently about a liter every 5 days). I use an old wine bottle cooler and a bubbler to keep it suspended for the doser.