I’ve had this whiskey barrel fountain for a few years and just recently decided to add some plants. This pond gets hot afternoon sun as it’s on our south-facing deck. I just got this water lettuce two days ago and it looks horrible- laying flat and yellow. The greenhouse I bought it from had it in the afternoon sun also so I thought it would be OK. Is it a goner? Dead? I went and bought another one yesterday, just in case, and it even has a baby attached and it looks the same as when I put it in the water. Should I throw the yellowed one away?? Help!