Jaume P. at 27.02.2018: It's working really well, especially to keep molly's fries until they can be left in the community aquarium. The option to leave the lower grid and the intermittent separation is not too efficient, at least for the molly. They do not have too much space and they stress too much the females. I have never used the option of putting the aerator, I have not needed it. Really a good buy!