As long as you haven't binned the sponges you're ok
Oh that's OK then, I transferred the sponges to the new filter, so that filter now has the old sponges, new carbon and new ceramic little thingies. I kept the new sponges, planning to replace each of the old ones separately after a month or two.
I'll do a water change later in the week and test the water to see if it's OK.
