Wow! How did you determine your application rate and did you monitor ph as you went. I've been playing with Alum to control algae but am reluctant to apply enough to be effective because of the potential ph crash. By the way, where did you get your shepard. Until last year I had a male that looked just like yours and have been looking for a replacement.
Moryan, you can do some searches on the amount of alum per volume and visibility. The best way is using a diluted mixture of water and alum to see how much it takes to clear a gallon of water. I will try and find a formula. You can add 60-75% as much hydrated lime as alum to maintain the ph.
