Changing Carbon Medium

[ggrowney]

My filter medium is bagged carbon along with ceramic balls and rubber. The manual recommends changing the carbon monthly. Won't this cause an ammonia spike every time?

[patoloco]

Carbon works as a mechanichal and chemichal filter medium, but after a short time it becomes clogged and stops working. You might want to replace it every month. This will not necesaruilly mean an amonnia spike, since you also have other filtration material thet hold bacteria as well.

But, you might consider stop using carbon. It works for a very limited period of time, and unless you have something ugly in the water, you don't need it. Most people use it only to remove medicines left after a treatment, ot to remove tannins leached into the water by driftwood.

[Rbishop]

I use carbon in all my tanks, all the time, except during rare periods where I need medicines. I change it out weekly, without fail. I feel the clarity it gives to the water is unsurpassed, IMO.

[born2lovefish]

I am starting to realize that carbon does not do too much. This month one the fish magazines had a couple page article on carbon. Everyone should read it. If ther water in nature does not use carbon to filter the water, why should anyone use it in their tank(s)?....

[mrgrudge]

Well, we can only replicate nature so much. A river environment, for example, is continuously refreshed with new water while our tanks are not. The carbon filtering helps keep the water a bit cleaner so we don't need to change it so often.

Of course, your mileage may vary.

[born2lovefish]

I understand that, but carbon does not take everything out of the water. And if you do not change it after it goes bad, which you have no way of knowing when it does go bad, the cardon will just release everything back into the water.

[joephys]

It all depends on how much stuff is in your water. Carbon also acts as a great bio medium. Carbon will often last for only a week or two, but it can last a month. I don't use carbon and my water is fine. IMO most of the ammonia eating bacteria are in the tank itself. I have completely changed filters (not just media, but whole hob filters) with no ammonia spike.

[Onikun]

I don't use carbon. haven't for over a year. i only use carbon to remove medication.

[mrgrudge]

I understand that, but carbon does not take everything out of the water. And if you do not change it after it goes bad, which you have no way of knowing when it does go bad, the cardon will just release everything back into the water.

It doesn't magically release everything at once the moment it is finished, it just stops absorbing any more. It takes quite some time to degrade and slowy release what it held.

[carpguy]

Carbon makes a good (very) short term chemical filter. It doesn't last a month, it doesn't last a week or two: it lasts a few days at best. It doesn't degrade slowly over time. It doesn't leach nasties back into the water column.

It removes certain chemicals and leaves others behind. Good for removing medicines, also removes fertilizers (if you're planted). Doesn't remove the need for water changes (and is generally a lot more expensive than fresh water).

It does make a nice mechanical filter and a nice biofilter after the chemical filter has filled up (think 48-72 hours). No harm in leaving it be. If you want to have steady chemical filtration you'd need, like rbishop, to change it out weekly, if not more often.

Changing it shouldn't result in an ammonia spike: if it does you've got other problems.

I more or less never use it (and am very happy with the clarity of the water).

[cyberbeer65]

Read this thread,there is some good info on carbon here.....

http://www.aquariacentral.com/forums/showthread.php?t=48909&highlight=truth+activated+carbon

[raymgnz]

If not carbon then what? I have a marineland magnum 350 canister + a bio wheel 350. I stagger them so I change 1 every two weeks. I thought the carbon helped remove the bio waste. What else can you use?

[joephys]

Carbon doesn't remove bio waste, bacteria removes bio waste. Carbon removes other toxins, heavy metals. The best way to deal with them is water changes.

[raymgnz]

How come the LFS doesn't know this? Thanxs for the info.

[sumthin fishy]

two things there ray. The LFS doesnt pay enough for a emplayees who know what they are doing. In the case that they do have knowledgable employees, they will loose money by telling us a specific product is not needed.

[carpguy]

(from an article (http://web1.msue.msu.edu/imp/modwq/wq239201.html) posted at Michigan State University) Many organic compounds, such as chlorinated and nonchlorinated solvents, gasoline, pesticides and trihalomethanes can be adsorbed by AC (Activated Carbon). AC is also effective for removal of chlorine and moderately effective for removal of some heavy metals. Metals that are bound to organic molecules will also be removed by AC. Fluoride, chloride, nitrate, hardness (calcium and magnesium) and most metal ions are not removed by AC to any significant degree.

As always, the Skeptical Aquarist (http://www.skepticalaquarist.com/docs/filtration/chemfil.shtml) has a good summary.

Its too long to quote in full but the short form: many organics including medicines, tannins and solvents: yes. Metals: maybe, some, others not so much. Other stuff (including nitrates) no. Leeching: it'd be really unusual; generally no.

It does do useful stuff and if you understand what it does you can use it for that. It causes no harm (unless your planted): if you don't mind paying for it you can put in a fresh batch every couple of days. Its not necessary and doesn't perform miracles: you still need regular partial water changes. You can leave it be after its no longer chemically active: it makes a nice home for the biofilter and a good mechanical filter, although floss is much cheaper.


How come the LFS doesn't know this?
Floss is much cheaper.

[born2lovefish]

How come the LFS doesn't know this? Thanxs for the info.

Why should they tell you if they even know....They want your money...

[Rbishop]

Ray...all I use on the 55 gal and up are Mag 350's. Some have been upgraded with bio wheels. I like the carbon in all of them. Your bio wheels are great...every body affirms what works for them. Doesn't mean the carbon hurts. I also use UG in all tanks and some say RUG only or no UG at all. I also like sponges in the smaller tanks. Don't take one position as the only way. To many variables.

There are different ways to achieve goals, just as the natural world produces different enviorenments for similar species.

What works for some will not work for all.