Planted Tank Obsessed
Join Date: Dec 2010
Location: Binbrook, Ontario, Canada
KNO3 is not illegal here (at least not in small quantities). It is illegal to ship it across borders without a swath of permits so you probably cannot order it from the US.
I get mine from a Hydroponics store local to me. Find one and ask the owner they should be able to get it no problem. The one I have been using is produced by DNF or "Dutch Nutrient Formula". They have a "six" pack of dry ferts including Potassium Nitrate, Mono Potassium Phosphate, Potassium Sulfate, Trace elements (very close to CSM+B in formulation), along with magnesium sulfate and calcium Nitrate (which I use rarely, and they do not need to be included in the "Six Pack".
Oh yea - The price is very reasonable. All 6 containers run about a total of $35 for 500grams of each.