I ran an ASM g3 recirc on my old 90g, in fact I still have it, a friend is using it on his 90g system, and is still feeding it from the overflow as I did. It works just fine. It is JMO but when looking for a skimmer, if it claim it will skim up to 100 gallons, I'd get the one that claims it would do 200 gallons. I've found they are good at under-rating there product when it comes to skimmers. again that's JMO.