Hal wrote:

You have pointed out something I've missed and must be ignored in many
gardening circles, since breaking down ammonia has long been a source
of fertilizer, but it begs the question where do you obtain these bulk
chemicals. I've never looked for them and doubt my gardening center
carries them, but would appreciate your help as to where to look.

Ammonium nitrate is an awesome fertilizer for anything but a body of
water containing fish - that's why most gardeners don't look any
further. Even with fish, your biofilter SHOULD convert trace amounts of
ammonium you add. It's just so darned toxic until it's converted that I
prefer to avoid it entirely.

I buy pound quantities of bulk fertilizers from
http://www.aquariumfertilizer.com/. My pond is 3 half-barrels (only
about 90 gallons), so a pound of each chemical has lasted me for two
years and I've still got some left. The salts are so cheap that
shipping them often costs more than the chemicals.

For potassium nitrate (KNO3) locally, look for stump remover at the
hardware store. If you've got a local chemical supplier, you can get
all the salts there. You may get an interesting expression if you ask
for bulk potassium nitrate - it's common name is saltpetre and it makes
nice explosives and fireworks. ;-) Check hydroponic suppliers for good
iron/trace element fertilizers. Some also have the bulk salts.

--
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