Not knowing what brand you bought from the local stores I would say that a good rule of thumb is to take twice as much as you would the Utopia Silver UNLESS you ended up with one of those high PPM products that contain 50 to 500 ppm of silver. That is far too much - anything over 20 ppm will result in clumping and likely has large particle silver.
For Utopia Silver and really bad candida or other serious and systemic conditions you would be best advised to take about 4 ounces a day the first few days and then two after that until you feel completely better, at which point you can reduce gradually to a couple of teaspoons to a couple of tablespoons. Adjust your children's dosage proportionally according to their weight (consider 150 pounds to be the adult size).
Don't forget the coconut oil, bentonite clay, probiotics and plant derived trace minerals.
And be sure and let us know how everything works for you and your children so more people can see how well quality and quantity colloidal silver works for candida.