Please help!! Recently bought my daughter a Glofish tank, 10gallons. We've had it up and running for a couple days, tested our water at petsmart. Tank is now ready to add fish. Now I've heard it's a MUST to clean pet store fish before adding them into a tank. I's this necessary? Ive heard to let store bag with fish inside, sit inside tank water to adjust temperatures then adding these fish directly into tank. What do u suggest we do?