Hi Clara congrats for the new stuff since the plant is monopodial type if possible avoid to use sphagnum as a medium they prefer dry at the root levels after watering. Usually the vendor during the delivery always covered with sphagnum to prevent severe dehydration. So the plant already with you remove the spag and use charcoal or bark with the multiple holes over the pot.Watering twice or once a day depending on your climate wet season once or winter better once a week or looks the plant condition. One thing I'm in doubt about the plant above to me it doesnt looks like Aeredis houlletiana because the purplish color doesnt matter I hope he will reward you beautiful flowers later.