As with other full sized skimmers there is quite a big variation on worth on this little skimmer. I have three and they do work but water level i the tank needs to be dead constant for them to work right.....so ATO is mandatory for best results and fewer headaches. Evenw ith ATO yur gonna get headaches but there is usually light at the end of that tunnel with any problems they cause. .....how long that light stays on is anyones guess,. As already stated the elbows are problematic, but most every other part of it is fine. SOme say the pump is in need of a better one others say its fine. So far knock on wood mine allhave been working like a champ since I installed them, however they do not come close to working like my home brew skimmer does......
The LFS here in town has sold a truck load of them skimmers and has had very few complaints that he revealed to me, but where he used to have a bunch onthe shelf before is now stocked with other products so that may be telling me something that he is not.