I just started my freshwater tank on new years added some decorations and live plants, bought 4 guppies and they all passed about five days later one by one. I took the water to be tested and I was told it is fine so just got one lovely back Molly and one Meri Gold about 24 hours ago. The advise was only to get the two (for a month) and they both looked happy and lively in the stores tank. After introducing them to the tank so far the Meri Gold seems to be doing OK, at least she is moving around; exploring some, but the Black molly is just parked behind the filter, this morning he was parked near the heater (both at the top). I've turned the lights off last night and now as I get home to hope that helps, any advice, how long do fish remain stressed and when should I worry if BM does not start exploring. BTW, they did have a small meal last night. Please advise.