How much gfo in a media bag?

[Visionist]

I have a 20g long tank with algae problems, there is a 10g sump. How much High capacity GFO should I use for this tank?

[Bingo1213]

Honestly I would not put any in a media bag. It does not work well in this manner due to the fact that it needs to tumble lightly in order to not clump and remain effective. You could try phosgaurd as that does better in a media bag. But if you must use GFO I would add about 1/4 to 1/2 a cup. But as I mentioned earlier it might not work. You could also get a cheap BRS media reactor, I have one and they work great! I think they run 30 to 40 bucks.