Hi. I have a new tank which has been running for a week with heater & filter. My pet shop is saying it will now be OK to add Tetra Neons, is this true? Reading most articles it would seem I have to wait for the cycle to complete (I'm just waiting for delivery of the API Master test kit)? Although some articles have said that 1 or a number of small fish would help kickstart the cycle? What should I do? & should I add live plants? My aquarium is 25 litre. Thanks in advance.