hi all, just been given a river reef 65lt, saved half the water to put back in then topped up with clean water and added fresh start to remove the chlorine etc but the trouble is i have well over dosed with the fresh start,put 5mil to 1.1 gallons instead of 1mil will i have to take all the water out again and start from fresh or will it be ok,need help quickly fish are in a bucket,thanks (filled half the tank with fresh water)