Lots of growth.

It is a mesh media bag. I ran it for 4 days and waited a day and just put more in today and did a 5 gallon water change

 

It sounds like your on a to a good start to get this cleaned up. I was battling cyano and brown slime for awhile. I would try one thing at a time to fix the problem but nothing ever changed. The only success I had was when I tried all the "remedies" at once. Physically removed as much as I could, changed the lights, added more macro algae, increased flow, added a GFO reactor, replenished my cleanup crew and did water changes more frequently. All those things at once drastically reduced the amount of ugly algae. It's amazing how much frequent water changes will help. (I was really bad about this. lol)

 

How long can or should I use the phosguard?

 

To be honest I have never used Aluminum Oxide (phosguard) and dont know the major difference (if any) between that and Granulated ferric iron oxide hydroxide. I run GFO on my tank constantly. I use as little as possible to keep the phosphate at zero, I was using a bit more when I was actually trying to lower my phosphates.