I to am running a 80 lagoon (6 weeks old), I used a brightwell xport bio brick in a 10 gal tank with MicroBacter7 for about a week at just room temp 70 deg water prio to installing it in my tank. I just started Chaeto (algebarn) about a week ago. Remember one thing there is no replacement for surface area. my buddy is also building a similar tank and used CaribSea rock, he has had a major bloom in his tank for about 5 weeks. After talking to the own of brightwell about his bloom he told him to add more bio blocks ( he has 6-2" blocks) in his tank because the caribsea rock is mostly mortar and is not pours for Bactria to grow. Im running the up to 1000 gal brick in my tank and it is super clear and every thing is spot on.