Tie with fishing line.. glue it.. all are okay. I would encourage it to holdfast to a spot you like as opposed to a darker area.. as mentioned above. Codium seems to like a lot of light, how much have you got over this tank? It also doesnt seem to be a very fast grower, not for me. It will...
I havent bought from them but know the owner, very nice guy, and have done trades with him previously. Send him a few emails if you're wary and I'm sure you'll agree with me. He really does have some great, and rare, macros that you dont often see. We still havent been able to find a species...
Actually the calcerous macros - like Halimeda (cactus algae, or money plant) do really well in reef style setups and do NOT take over. They can sporulate (go sexual) but the potential is very very remote and the warning signs are obvious.. small green balls will form on the algae before it...
