That's beautiful, I'm about halfway there .When I first started the refugium, I was just letting it grow out because I had lots of open space. After about six months, I started removing a substantial amount to "export" the nutrients. After a few months of doing this, nitrate and phosphate levels started to creep up so I decided to leave it alone again. For the past two or three months I haven't messed with it and levels have come down again. Anecdotally, this seems to suggest it is best for me to leave it alone and just let it do whatever it is doing down there. I haven't removed any and it is so dense it's hard to know what is going on down there.