Activated carbon lifespan

Hi folks,

I use activated carbon in a power filter for my aquarium. I probably
don't really need it since I do 20% water changes each week anyway, but
I like to have the water as free of impurities as possible and it does
seem to make it smell cleaner :-) I'm interested in knowing how to tell
exactly when a batch of activated carbon has absorbed as much organic
waste as it can hold and has reached the end of it's lifespan. I
regularly change it every month, but I don't like having to guess as the
stuff is probably still good and I'm wasting money and effort and
throwing away whatever beneficial bacteria has gathered on the granules.

I'd also like to know if it can be easily cleaned and recharged. I read
in a few places that the absorbed waste material can be separated from
the carbon by baking it at a high temperature but I can't find the
details of the process. Can it be done in my oven at home? Also, is it
possible that by tapping and breaking the carbon granules with a mallet
you can expose fresh unused areas of the carbon and extend it's life
that way?

Thanks for any tips!

- Logic316


"Bureaucracy: The process of turning energy into solid waste."

On Wed, 20 Jul 2005 02:46:05 -0400, Logic316
wrote:

Hi folks,

I use activated carbon in a power filter for my aquarium. I probably
don't really need it since I do 20% water changes each week anyway, but
I like to have the water as free of impurities as possible and it does
seem to make it smell cleaner :-) I'm interested in knowing how to tell
exactly when a batch of activated carbon has absorbed as much organic
waste as it can hold and has reached the end of it's lifespan. I
regularly change it every month, but I don't like having to guess as the
stuff is probably still good and I'm wasting money and effort and
throwing away whatever beneficial bacteria has gathered on the granules.

I'd also like to know if it can be easily cleaned and recharged. I read
in a few places that the absorbed waste material can be separated from
the carbon by baking it at a high temperature but I can't find the
details of the process. Can it be done in my oven at home? Also, is it
possible that by tapping and breaking the carbon granules with a mallet
you can expose fresh unused areas of the carbon and extend it's life
that way?

Thanks for any tips!

Peter Hunnam writes in his book that to reactivate the carbon you need
to bake it at 500C (932F) in the absence of oxygen. So you probably
can't do this at home.

He also suggests that you can add a few drops of Methylene blue to the
intake of your filter; if the carbon is exhausted you will see a blue
color in the water returning from the filter.

-Derek

"Derek Benson" wrote in message
...
On Wed, 20 Jul 2005 02:46:05 -0400, Logic316
wrote:

Hi folks,

I use activated carbon in a power filter for my aquarium. I probably
don't really need it since I do 20% water changes each week anyway, but
I like to have the water as free of impurities as possible and it does
seem to make it smell cleaner :-) I'm interested in knowing how to tell
exactly when a batch of activated carbon has absorbed as much organic
waste as it can hold and has reached the end of it's lifespan. I
regularly change it every month, but I don't like having to guess as the
stuff is probably still good and I'm wasting money and effort and
throwing away whatever beneficial bacteria has gathered on the granules.

I'd also like to know if it can be easily cleaned and recharged. I read
in a few places that the absorbed waste material can be separated from
the carbon by baking it at a high temperature but I can't find the
details of the process. Can it be done in my oven at home? Also, is it
possible that by tapping and breaking the carbon granules with a mallet
you can expose fresh unused areas of the carbon and extend it's life
that way?

Thanks for any tips!

Peter Hunnam writes in his book that to reactivate the carbon you need
to bake it at 500C (932F) in the absence of oxygen. So you probably
can't do this at home.

He also suggests that you can add a few drops of Methylene blue to the
intake of your filter; if the carbon is exhausted you will see a blue
color in the water returning from the filter.

-Derek

To add to the information, some filters (many HOBs) move the water too
quickly past the carbon for the meth. blue test to be really representative,
so with some models, don't be surprised to see fresh carbon fail this
particular test method. The working life expectancy of carbon really
depends on the quality/condition of the water, so filtering RO or municipal
water will give very different results. In the trade, we use 3 weeks as a
reasonable life expectancy for home filtration system, and 6 to 12 months
for commercial systems. That was interesting about the 500C bake requiring
an absence of oxygen (not that I would have tried it anyways ;~).
--
www.NetMax.tk

NetMax wrote:
"Derek Benson" wrote in message
...

On Wed, 20 Jul 2005 02:46:05 -0400, Logic316
wrote:


Hi folks,

I use activated carbon in a power filter for my aquarium. I probably
don't really need it since I do 20% water changes each week anyway, but
I like to have the water as free of impurities as possible and it does
seem to make it smell cleaner :-) I'm interested in knowing how to tell
exactly when a batch of activated carbon has absorbed as much organic
waste as it can hold and has reached the end of it's lifespan. I
regularly change it every month, but I don't like having to guess as the
stuff is probably still good and I'm wasting money and effort and
throwing away whatever beneficial bacteria has gathered on the granules.

I'd also like to know if it can be easily cleaned and recharged. I read
in a few places that the absorbed waste material can be separated from
the carbon by baking it at a high temperature but I can't find the
details of the process. Can it be done in my oven at home? Also, is it
possible that by tapping and breaking the carbon granules with a mallet
you can expose fresh unused areas of the carbon and extend it's life
that way?

Thanks for any tips!

Peter Hunnam writes in his book that to reactivate the carbon you need
to bake it at 500C (932F) in the absence of oxygen. So you probably
can't do this at home.

He also suggests that you can add a few drops of Methylene blue to the
intake of your filter; if the carbon is exhausted you will see a blue
color in the water returning from the filter.

-Derek


To add to the information, some filters (many HOBs) move the water too
quickly past the carbon for the meth. blue test to be really representative,
so with some models, don't be surprised to see fresh carbon fail this
particular test method. The working life expectancy of carbon really
depends on the quality/condition of the water, so filtering RO or municipal
water will give very different results. In the trade, we use 3 weeks as a
reasonable life expectancy for home filtration system, and 6 to 12 months
for commercial systems. That was interesting about the 500C bake requiring
an absence of oxygen (not that I would have tried it anyways ;~).


With oxygen, you get a pile of ash and some CO2 rather than carbon. ;-)
To keep adding to the info, high temperature is how carbon for aquaria
should be activated in the first place. Cheap carbon is sometimes
activated with strong phosphoric acid instead and leaches phosphates
into the tank water. One of the first things to check in a tank with
high phosphates is the carbon (put a few granules into a sensitive
phosphate test set up with distilled water).

Good carbon should already have its pores exposed to water, so breaking
the granules with a hammer will only get you a mess.

--
Elaine T __
http://eethomp.com/fish.html '__
rec.aquaria.* FAQ http://faq.thekrib.com

You can safely assume that the activated carbon is spent after one
week. After that it's simply a biological filter medium (and not a bad
one at that).

Yes, one week. No, not kidding.

Methylene blue will work to test the carbon, but is toxic to plants.
Just a thought.

Regenerating activated carbon is rarely if ever worth it. I'd suggest
running carbon once every few months, for one week at a time, then
discarding the carbon (it's good for compost, if you're in to that
kind of thing).

Mean_Chlorine wrote:
You can safely assume that the activated carbon is spent after one
week. After that it's simply a biological filter medium (and not a bad
one at that).

Yes, one week. No, not kidding.


Wow. But wouldn't that greatly depend on the volume of the aquarium, as
well as the amount of life it supports? In my case, I'm using a 2
gallon aquarium housing 1 betta, 1 ghost shrimp, 1 ramshorn snail, and
some live plants; and the power filter I'm using is an Aquaclear 150
designed for up to a 30 gallon capacity (with the flow turned all the
way down to prevent excessive current).

- Logic316


"Don't get excited about a tax cut. It's like a mugger giving you back
fare for a taxi."
-- Arnold Glasow

On Wed, 20 Jul 2005 02:46:05 -0400, Logic316
wrote:

Hi folks,

I use activated carbon in a power filter for my aquarium. I probably
don't really need it since I do 20% water changes each week anyway, but
I like to have the water as free of impurities as possible and it does
seem to make it smell cleaner :-) I'm interested in knowing how to tell
exactly when a batch of activated carbon has absorbed as much organic
waste as it can hold and has reached the end of it's lifespan. I
regularly change it every month, but I don't like having to guess as the
stuff is probably still good and I'm wasting money and effort and
throwing away whatever beneficial bacteria has gathered on the granules.

I'd also like to know if it can be easily cleaned and recharged. I read
in a few places that the absorbed waste material can be separated from
the carbon by baking it at a high temperature but I can't find the
details of the process. Can it be done in my oven at home? Also, is it
possible that by tapping and breaking the carbon granules with a mallet
you can expose fresh unused areas of the carbon and extend it's life
that way?

Thanks for any tips!

- Logic316



I quit using carbon about 2 years ago. I noticed that I couldn't get
the water flow back after cleaning the cartridges, so I made a slit
and removed the charcoal then cleaned the media. Sure enough, the
charcoal was not comming clean. About the same time I noticed others
posting that charcoal was not so necessary, so I took charcoal out of
my tanks. I have no regrets.

It may be my nose ain't so good, but I do not have any noticeable
odors in my tanks and they are all clear to look at. The few times I
have tested the waters, they all test good.

I rely on changing the tanks water 20% twice weekly. I take the water
straight from the tap, no chemicals added.

Unless someone just feels more comfortable using more complex methods,
I prefer "KISS" or "keep it simple, stupid." It is an old tried and
true philosophy.

dick
"Bureaucracy: The process of turning energy into solid waste."

If you simply have to have osmehting to keep purifyiing water, try any
of the new compounds out there like Purigen.....I have not used ac in
years myself and have nbever looked back. I use purigen for 3 or 4
days in the tanks once a month or so........Its completely
rechargeable so there is no continual expense of buying and throwing
out ac.......A proper running and setup filter/tank should really
eliminate a need to run it 24/7/365.

On Wed, 20 Jul 2005 02:46:05 -0400, Logic316
wrote:

===Hi folks,
===
===I use activated carbon in a power filter for my aquarium. I probably
===don't really need it since I do 20% water changes each week anyway, but
===I like to have the water as free of impurities as possible and it does
===seem to make it smell cleaner :-) I'm interested in knowing how to tell
===exactly when a batch of activated carbon has absorbed as much organic
===waste as it can hold and has reached the end of it's lifespan. I
===regularly change it every month, but I don't like having to guess as the
===stuff is probably still good and I'm wasting money and effort and
===throwing away whatever beneficial bacteria has gathered on the granules.
===
===I'd also like to know if it can be easily cleaned and recharged. I read
===in a few places that the absorbed waste material can be separated from
===the carbon by baking it at a high temperature but I can't find the
===details of the process. Can it be done in my oven at home? Also, is it
===possible that by tapping and breaking the carbon granules with a mallet
===you can expose fresh unused areas of the carbon and extend it's life
===that way?
===
===Thanks for any tips!
===
===- Logic316
===
===
==="Bureaucracy: The process of turning energy into solid waste."


==============================================
Put some color in your cheeks...garden naked!
"The original frugal ponder"
~~~~ }((((o ~~~~~~ }{{{{o ~~~~~~~ }(((((o

~Roy wrote:
If you simply have to have osmehting to keep purifyiing water, try any
of the new compounds out there like Purigen.....I have not used ac in
years myself and have nbever looked back. I use purigen for 3 or 4
days in the tanks once a month or so........Its completely
rechargeable so there is no continual expense of buying and throwing
out ac.......A proper running and setup filter/tank should really
eliminate a need to run it 24/7/365.


That Purigen stuff sounds pretty good, though I have to run my overhead
filter anyway since that's what aerates the water.

- Logic316



"Life is either a daring adventure or nothing. Security is mostly a
superstition. It does not exist in nature."
-- Helen Keller

The nice thing about compounds like Purigen is they are reuseable. The
initial outlay of $$ may be higher, but its much cheaper in the long
run in terms of $$ and time.
Purigen (made by Seachem is good) Approx 5 oz is sufficient to handle
up to 250 US gallons, so you can see it takes very little for say a 55
gal tank. On average its useable life span before needing to be
rejuvinated is approx 6 months of continuous use.......Its easy to
tell when it needs rejuvenating as it changes from the white color to
a dark brown........Rejuvinating it is simple as regular household
chlorox is used to soak it in, and then rinsed, followed by a soak in
dechlorinator dosed water, and its ready togo within 24 or so hours...

You can find it in already packaged mesh bags, or in plastic bottles.
It does need to be placed in a very very fine mesh bag as its about
the grain size of sugar, so the prepacked mesh bags are nice as it
already comes with the bag. I use a piece of the fabric from nylon
hose to make a bag which is fine enough to keep it inplace and buy it
in the bottle as its much cheaper that way. Purigen is supposed to be
over 500% more effective at removing impurities and odors etc than any
other typically used product.

On Wed, 09 Nov 2005 15:28:51 -0500, Logic316
wrote:

===~Roy wrote:
=== If you simply have to have osmehting to keep purifyiing water, try any
=== of the new compounds out there like Purigen.....I have not used ac in
=== years myself and have nbever looked back. I use purigen for 3 or 4
=== days in the tanks once a month or so........Its completely
=== rechargeable so there is no continual expense of buying and throwing
=== out ac.......A proper running and setup filter/tank should really
=== eliminate a need to run it 24/7/365.
===
===
===That Purigen stuff sounds pretty good, though I have to run my overhead
===filter anyway since that's what aerates the water.
===
===- Logic316
===
===
===
==="Life is either a daring adventure or nothing. Security is mostly a
===superstition. It does not exist in nature."
=== -- Helen Keller


==============================================
Put some color in your cheeks...garden naked!
"The original frugal ponder"
~~~~ }((((o ~~~~~~ }{{{{o ~~~~~~~ }(((((o