If you do decide to seal those in, you will need something to do deep cleaning once a week. I have a hand held steamer that works great ! I steam all the tiles, and then I take paper towels and wipe up the moisture. Allow to air dry, and replace all furniture and dragon !
If you don't seal those in, then you can remove them and wash either in the dishwasher no detergent, or in the sink. Just make sure if you use the dishwasher, to run it a time or two before the tiles, no detergent, to flush out any residue from previous washes.
Hope this helps !
Janie.