Tracy, that's what I don't have, experience

. I know Rex is on the road but I hope he chimes in. Alum/Lime treatments being one of his specialties I would guess he's tried about everything. He told me he just treated a 20 acre foot, 3 acre pond with his alum tank in front and lime tank in back. In both tanks (IIRC) he created a way to "churn" the mixtures in each tank. So if his "paddle" keeps everything churned, maybe there is a way to mix the two together which I think he's trying. (Rex, forgive me if I'm butchering up our discussion!)
He used the analogy (mixing alum and lime) of mixing starch with water. If you let it sit, even for a short time the starch will settle. Keep mixing it and it stays suspended.