First find the current rate the hose pumps by multiplying its normal rate by 2/3: 6 gallons/minute * 2/3 = <<6*2/3=4>>4 gallons/minute
Then divide the number of gallons in the pond by the number of gallons pumped each minute to find how many minutes filling the pond takes: 200 gallons / 4 gallons/minute = <<200/4=50>>50 minutes
#### 50