SO I battled algae in my nano then in my 60 and I found the best cheapest way is to build a cheap ATS for instructions on a bucket style on go here.
http://www.monsterfishkeepers.com/forums/showthread.php?t=180385&highlight=mega+powerful
Every week I would take a tooth brush and get any algae off my rock work. It took me about two months to be algae free.
cooking your rock is an option but more time, work, and money than building a ATS
Also remember that phosphates are stored in your LR and in the algae so test kits may come up with low numbers but still have unwanted growth. Since your LR will take some time to leech out all the phosphates there is no quick cure here and choosing a course of action and sticking to it for at least two months is the way to go.
http://www.monsterfishkeepers.com/forums/showthread.php?t=180385&highlight=mega+powerful
Every week I would take a tooth brush and get any algae off my rock work. It took me about two months to be algae free.
cooking your rock is an option but more time, work, and money than building a ATS
Also remember that phosphates are stored in your LR and in the algae so test kits may come up with low numbers but still have unwanted growth. Since your LR will take some time to leech out all the phosphates there is no quick cure here and choosing a course of action and sticking to it for at least two months is the way to go.