About 3 weeks ago the mantel on my clam was not as pronounced as before. It was at the bottom of the Hex 30 inches on the sand. I thought maybe it needed more light so I moved it up. It jumped right back down. For the past three weeks it’s been fine. The mantel never returned to full open as before. Now for the past week it's been laying on it's side. Seems ok still highly reactive shuts quickly with just the sense of a shadow. Is this normal to be on it's side??