to lower my high nitrates i bought some macro algae. since my nitrates are off the chart the LFS told me that I can just put this algae right in my tank. so thats what i did. is this ok? see pic below. it appears to be codium algae.
I think it is a codium species, too. Maybe C. fragile? I put a piece between rocks and it still hasn't attached, so I have tied it down with fishing line. I have heard some say you can super glue it.
But, I only did that for aesthetics. I think it would still reduce NO3 just floating, as long as it is growing. It might not grow as well if it goes to a dark spot...
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 still move some NO3 for you but it might not make a big dent.