I have an arched piece of mopani that I put in my tank about two months ago. I attached a big mat of java moss, an anubius and a java fern with fishing line. About two weeks ago I removed the fishing line. The anubius and fern are thoroughly attached, but the moss was only attached around the edges where it's grown. When I put it in the water it bulged and, after a few days, started to pull loose in places. I trimmed and retied it. What do I need to do to make it stay on? It's tied on with fishing line, but I'm afraid one of my fish is going to get caught in the line and hurt itself. The wood is an arch, with moss on top, so there is line on the underside that the fish could potentially get caught in. Should I have pulled the mat in pieces and attached them instead of putting it on as one big piece?