Using an aquarium pump and a 2 micron stone for aeration. Puts a bit of foam on the top of the beer after about 30 min, but wondering if it may not be powerful enough. Was hoping for it to finish around 1.012-1.013
I won't attempt to comment on whether your aeration stone is working but I came across this in Jamil's Yeast book and thought it may be something to consider.
White Labs ran an experiment injecting pure oxygen into 5.3 gallons of 1.077 wort using a .5 micron stainless steel sintered stone at a flow rate of 1L per minute. The results show that to reach the desired 8 to 10 ppm, you would need to inject oxygen for only one minute.... Increasing the level of oxygen past 9ppm did increase the pace of fermentation slightly for the first 3 days but both ended at the same terminal gravity....Research also indicates the addition of oxygen at 12 hours into your lag phase increases fermentation speed by 33 percent...
I'm not exactly sure how this applies to your setup but they were able to get 9.2ppm after only 60 seconds using pure O2. Hope this helps