sneeyatch,
Thanks for sharing your experiment.
You have treaded into possibly dangerous territory with your experiment. That said, experimentation is how we learn to use the tools we have available to us more efficiently. The kind of experiment you are running is usually done with inhabitants you can afford to loose. Personally I would not hesitate to use AF at higher than recommended doses if I did not have fish, coral or other occupants in my tank, like when first starting out. The AF does brake down quickly, within 24 hrs.
In my field of study, Universities experiment with herbicides to try and control stubborn weed pests, like poison ivy for example. They found that much higher doses of Round-up worked well to control it. As a result the manufacturer put more money out to get the new label for Round-up at twice the strength to control poison ivy. Comparing land herbicides to reef herbicides is completely different, since you can't apply the product directly on the target without getting it on the non-target organisms.
With what I have read about AF, you don't want to increase the strength of it. Increasing the strength of AF has caused problems for some hobbyists in this thread. Increasing the frequency as you have done, may be helpful, but only time will tell.
Remember, any hobbyists who decides to experiment with AF are taking a chance of loosing valuable inhabitants.
If you are willing to take this chance, I am interested in following along and knowing exactly what doses, frequencies, tank inhabbitants, pests.....ect, you have in your tank.