I've fought with skimmers since I bought my very first one... it was an in-tank unit, clamped to the rim, ran off of a wooden air block and a Silent Giant air pump. As you might guess, that's been a few years ago. I've owned a great many skimmers since then, of all different quality and price levels.
At one point, I had a Precision Marine Bullet II skimmer, external, huge... Beckett injector design. Sounded like a jet engine warming up. But. It worked. Fantastically. Once adjusted and broken in, it was rock solid... for YEARS, without me doing anything but cleaning the skimate out once in a while.
I've had others, of various types, that had to be adjusted weekly, or even daily. Even had a couple that just plain didn't work (cough, cough, Skilter...) Honestly, most of them are touchy, hard to adjust, and don't stay adjusted.
But... A skimmer is the one and only mechanical method of filtering a marine aquarium that actually removes contaminates from the water column. Well... until recently... the rollermat devices do, as well. All other forms of mechanical filtration trap contaminates in the water column until YOU remove them. Add in the oxygenation and pH benefits that skimmers provide, and I consider them a very valuable filtration method... the only mechanical filtration method I use.
Today, I'm using a Vertex 180i. Yeah, it was expensive. The pump quit in just under a year, and the new part was also expensive, though their support did make every effort to assist me. This thing just _works_. It's quiet, nearly silent, much less bulky, and works every bit as well as the old Bullet II I had. Adjustment? I had to re-adjust it slightly when I replaced the pump. Aside from that, haven't touched it in over a year now. Empty the cup, rinse out the body twice a year, and it just runs.
I'm quite convinced. When it comes to skimmers, quality matters.
