I don’t know about the Cardas but I do use the HiFi Flux.
I do use 2 different things to clean my stylus, I use both the HiFi Flux and DS Audio ST-50.
I use the ST-50 after both sides of the LP and I use the HiFi Flux at the end of every listening session.
The HiFi Flux is very good and does a very good job.
I would recommend both the HiFi Flux and the DS Audio ST-50. Not necessary to have both, either one will do the job well, I just happen to have both.