R3000 switching from MK to PK

I have the newer carts which are self-setting. The PK is 1/2 full but indicator is low. Cannot switch back to PK from MK. Instruction says to refill??

Thanks

You will need a second chip (or put the old Epson cart in for a minute). Please read the warning on this product (in red): https://shop.inkjetmall.com/CISS-for-Epson-P600.html

Thanks,since there is a flush, should I fill the OLD cart with 10mml?

Gkl