General question for my first post here.
When selecting a filter, do I purchase based on Gallon capacity or flow rate? Currently I have a 55g with two penguin 200's. If the boxes read correct, two of these should have about 400 GPH and the ability for a 100g tank. (I tend not to believe manufacturer claims)
Stocked in the tank are 3 Jack Dempseys (3-4 inch) 1 Oscar (4 inch) and 1 Pleco( 5-6 inch).
50% water changes every two weeks at best ( i know i should do more frequently ) and the water is relatively clear for the time being. I haven't been having problems with the load but as these guys get larger i think it could get worse. I was looking into gettting an XP3 which is rated for up to a 175g tank and 350gph. I have heard that the rule of thumb is 10x Volume for HOB's and 4-5x volume for a canister, so for a 55g I should be at 550gph for HOB and 275gph for Canister. If these numbers are correct, I dont have enough filteration useing the twin penguin 200's. So do i look for the proper Gallon capacity or GPH ? Everything that i have been reading is that the XP3 is excellent choice and that tank maintence is extended due to the large amount of media used. Am I comparing apples to oranges with these different products? Can someone give more technical advice rather then an endorsement for the product please.
Thanks in advance


) is the best, though I later added the magnum 350 as well after going to a bigger tank. I think you have to keep in mind that if water just cycles at 500 GPH but is not really too well "purified" in the process, it's not so great but sounds good for "marketing"
