It could be a couple of things. I'm not sure how much direct sunlight are your plants getting. It could also be transplant shock. Watering once a week is ok but if the soil is still wet after a couple of days ie the pot is still got some more weight to it, then your plants aren't absorbing water which would likely lead to root rot. If that is the case don't water anymore. I had a banana plant in a pot over winter once which I placed by a window that got morning sun. Did not grow at all. So my neighbor who gave it to me said don't water it anymore. Eventually all the leaves turned brown and it was just a stalk. It didn't die. I put it outside when it was warm again and it eventually started putting out new leaves.