I have used it on 2 of my tanks works like a charm and the flow charts are spot on as well follow the guide lines in the stickies here and you will be happy
The aqualifter is life saver cause without mine it would have emptied my 75 gallon 3 times already and it keeps the siphon working at its maximum efficiency at all times. For about 20 bucks it is definitely worth it and I got mine with the prefilter off ebay. I also got a holder for it as well off ebay so you can say I spent about 25 bucks on mine.