Well, if you have pots that have drainage then you can flush without overwatering..all your doing here is dilute the Nutes thats still in the soil...Just try not to water until the soil dry's that way you can let your plant take in the water that still exist in the pot.

Flushing! the best example i can give you are your EYES..say if you got some soap in your eyes and it burns, you'd have to flush your eyes out until the soap vacants and your eyes stop burning...Catch my drift?