i don't like using sand in the soil. not that there is any problem with them.. just that with added weight, i can't tell when the pot is dried up. if it was just up potted, i would leave it alone and just monitor it. if you disturbed the root while moving it to black container, it might have taken some stress. with only sand and perlite in soil mix, i doubt that will hold enough water the cause any serious issue. i have succulents in peat moss, perlite and sand in 3:2:2 mix. i check the water level by sticking in a wood stick to see how wet it is every few days. that thing usually dries up within 3 days. and i typically water it every 5 days.