User blog comment:Shufflertoxin/How to Install Flux Buddies 2.0 Modpack/@comment-109.154.47.53-20160229175058/@comment-4682764-20160229201234

You may need to allocate more RAM to the game. This can be found under Settings, Java/Minecraft and then Maximum Memory/Ram. 2GB (2048MB) is recomended for this modpack.