hi Panda
I heard from Desi that her diatom reduction after using Coral Snow was quite fast.
2 days or so.
But pls do not misplace your trust on it as a miracle solution, bro.
If you have been using untreated tap water for topping up and WC, do expect some of these diatoms to show up.
New tank has diatoms easily as well. Proper husbandry chores, feeding regime, water conditions, etc also play a part.
It is good to use Distill water for topping up and WC.
But pls note that they have a PH of only 7.0
so overtime, your PH might slowly drop.
Good to keep an eye on PH.
cheers
jacky