For a new pond, set up your pond and filter, adding a measure of Wildlife Pond Tap Safe or Fresh Start when you fill. With the filter running (you can run your fountain or waterfall at this stage), leave it all to settle for a minimum of 24-48 hours to ensure everything is working correctly and allow the water temperature to stabilise.
Adding some Bio Start will help to kick-start the filter by adding the ‘friendly bacteria’ required to break down fish waste.
Spring and early summer are a good time of year to add new fish as they will have plenty of time to settle in and grow to a healthy size to face the cold of winter. Only add a couple of fish at a time to prevent overloading the filtration system. Do not overfeed your fish.