You can get a BRS reactor pretty cheaply used. They work really well. I find that whenever I try to DYI something it ends up costing more then I would have spent buying a decent piece of equipment used.
Have you measured phosphate level? and the results are?
How long has the tank been setup?
Do you use RO/DI water?
Water changes?
Lighting?
and so many other things could be the issue and could easily be fixed before resorting to GFO.
Its 100% normal for a new tank to experience algae outbreaks.. The tank isn't even close to "mature" yet..
What type of algae (or bacteria)?
Hair/bubble/cyano/diatoms/dinos?
Nothing wrong with trying GFO either though.. I've used a Phosban 150 .. works great IMO.. The BRS one is typically fine too.
Some people just react too quickly to a small algae outbreak and it will more than likely go away on its own.