If you only have the bonded synthetic stones that came with the ruixin, then I would suggest as soon as possible to get better stones as a start. They are awful, soft as butter and just disintegrate and makes a mess while you use them.
The Chinese diamond plated stones for the ruixin are much better than the other garbage stones they provide and they will serve most of your sharpening needs. Be sure just to use soapy water with them, they tend to work better and last longer if used with a small drip bottle of water mixed with a couple drops of liquid dish soap. Hopefully you also got a set of diamond plated stones with the plastic bases?
If you have a set of diamond stones on backings, then you're set to sharpen any knife, not just ceramic knives. Diamonds will sharpen any steel. Eventually you may want more variety of stones bit initially the diamond will be good for everything.
If you don't have the diamond plated and you're on a budget then have a look at getting the Chinese diamond plated stones if you didn't get a set with the Ruixin.
If you want to spend a bit more, then have a look at edge pro size stones on a web store like Gritomatic, they have a great selection.
Did you get the metal base version of the Ruixin pro, or the plastic base version?
Did you get the stone holder that takes 4 stones at the same time, or just 1 stone?
If you have the 4 stone holder, then definitely only one 1 or 2 stones in it maximum. If you install 4 stones, then one or two of them will always be loose due to the design.
I have some free 3d printable designs for upgrades and options for the Ruixin sharpeners, if you are interested then let me know and maybe it can help you.