Do those have sponges in the center? If so, it's not a good idea in my opinion as the sponge will deteriorate and you don't know what materials it is made from.
Toss in ceramics rinse the old stuff off to get rid of salt and all good. New bacteria will colonize and away it goes. The salt in the ceramics won't harm much as long as you don't have super sensative fish like discus or anything. Even then it will only be a minute amount of salt per gallon
i use 20 cent felt sheets in all my tanks for the mechanical and scour pads for my bio media. im on a budget as well. works very well. the felt clogs fast but is very cheap and is a great water polisher.