i have cs250 with get valve less then 2 month old that i am going to sell . i have one more cs83 that i am going to keep. becuase i want to upgrade to 240 gallon tank and i sure that this skimmer can handle on this size tank , today i have a small sump and cs250 with the get valve it's to tight and overkill . i think if you going to buy the rs250 it will be good for 250g tank.