Regular charcoal is completely different from activated charcoal. Regular
charcoal is made in a high heat, and low oxygen chamber. Activated charcoal
is exposed to oxygen at the last minute, just before it's cooled down. This
exposure to oxygen, makes the charcoal very porous, and it becomes a good
filter for small particles.

Regular charcoal, like chunk charcoal, is just blackened wood, doesn't do
much for the pond, maybe color the pond black from the dust. Charcoal
briquettes is crushed chunk charcoal mixed with binders, some additives to
regulate the burn rate, and other stuff. Briquettes definitely aren't good
pond material, and some would argue, not good bbq material either.

Sameer

"Jeff Lowe" wrote in message
...
Intro: I've been lurking for a few weeks and decided it's time to take the
plunge. My son was given permission to catch goldfish (net) at pond and
came
home with 6 very nice comets, ranging from 4 to 9" length. They have been
living in a 37 Gal tank (too small!) while we build a pond for them. We
purchased a 150 gal preform and have put it in the ground. I bought a 1400
gph pump at a fish auction and am starting to build the filter. I have
decided on a 55 gal barrel filter with an up flow gravel bed and plan on
having WH floating in the top as a veggie filter. I know that charcoal
briquettes are only sawdust and glue and some sodium nitrate to speed up
burning, and given this composition, are totally unsuitable for aquatic
use,
however, my local food Coop sells natural chunk hardwood charcoal with no
additives. Would this be effective as a filter material, at least while
cycling, and in the future to clear meds, etc?

Jeff Lowe