I made a Video on how we water our Desert rose plants in house ,we do this about every 3 days every 2 days if its hot and the soil is dry to the touch ,
We only ever leave them sat in the bowl of water for 20 minutes while they are watered
Any longer and you can do some damage to your plant
Although the area where we keep our desert rose plants is sprayed as we have other plants here too we do not specificly spray them it can lead to small brown dots or damage to the leaves if spraying directly