Depending on how big the plant is, you should be good with no nutes for a few weeks. I would use something with a 1-3-2 ratio(ie-5-15-10, 10-30-20) in a few weeks once you switch. You can also use a veg. nute the first time or two for a little nitrogen to begin with. You can feed it every other watering, around 1/2 of what the label says, but you have to watch the plant yourself to see if it needs more or less. You may need to buy some cal/mag also, if you don't have something already. Do you already have your nutes selected?