Changing Filter Cartridges

[Jones2w]

I have had my 55 Gal tank set up for about a month now (25 days to be exact) I know I should change my filter cartridges but I'm not exacly sure how. I have a marineland Biowheel 330 Power Filter (the one with two cartridges) My qyestions are:

1. Do I unplug the filter when I change the cartridges?

2. Do I change one at a time? one say today and the other in a week? I was thinking this to help offset the loss of bacteria during the change?

any advice will help

[theotheragentm]

Yes, I would unplug the filter when changing any filter media out. You have to on some filters, but the reason you would want to is because you are going to be displacing this filthy cartridge. There's no need to let it dump back into the tank. Alternating cartridges is a great idea. I would actually recommend just buying 100% polyester stuffing from a craft store or super store like Walmart. There's no need to use the special cartridges from the filter manufacturer. Carbon is unnecessary. Then you can just toss the stuff when it's extremely dirty.

[TomK2]

Since your set up is still young (at least at the time of the first post), I agree, alternate cartridges when changing. AFter your tank has been fully cycled for a few months, your biowheels should have enough colonization so that loss of surface area from changing even both cartridges will not be a problem. If your cartridge isn't dirty, then don't change it.