A few questions about tank

Alright will do

 

Oooops. Carbon is among the gently controversial subjects on FL. Some people, myself included, believe it should be used and changed every 3-4 weeks, others consider it a useless waste of money.

However, used carbon should be removed from your tank, because some say, there is a possibility that it will leach toxins. As a carbon user I don't care to experiment on my fish to prove or disprove this point. I remove used carbon.

 

I'm in the middle on carbon. I don't use it but I also don't think it's a complete waste of money. But it definitely becomes a waste of money if not changed monthly.

 

Definitely not a waste of money. I can see the difference in my tank. Once I forgot to put the activated carbon in for a while and when I discovered that I put in the carbon and it was very clear water. I need to buy more activated carbon now come to think of it.....

 

I'm old school & think using carbon regularly is a waste of money & to some extent a manufacturers ploy to make us spend more money, in the same way they tell you to change your filter media monthly which we all know is wrong.
Yes it has it's uses in the short term, for example taking out meds but as long as you have a good tank maintenance regime, water changes, filter cleaning etc then imo you don't need it.
Some brands btw contain phosphates which can lead to bacteria blooms, so if you use carbon regularly read the packet.

 

Definitely the filter media part is completely wrong. I just wash it, I don't get why you would need to keep buying mesh bags that could be washed.
At my store they sell them in large containers that are only $6.

 

Okay here is the deal with carbon.

Carbon has receptors on it that bind meds, impurities, etc. In 3-4 weeks those receptors become saturated.

The carbon does not completely stop working. Nor does it truly leech toxins back into the water.

What it comes down to is binding affinity. If a new impurity comes along with a higher binding affinity than the one the carbon is already saturated with, it will knock it off and replace it, sending the old impurity back out into to water.

I do not recommend leaving the carbon in if it has expired. There is no way to know what likes to bind more than whatever else.

I don't use carbon personally but I am excited to try Purigen. I also do keep carbon on hand in the event I need to medicate the tank then pull it out or anything. It's my opinion that I can replace carbon with biomedia and I would rather have that.

But if you are diligent in it's removal then it's really a matter of preference.

 

Well said PI, I didn't know about the binding affinity and the potential swap of particles.
I thought once an impurity was bound then that was it.

I also don't think carbon will leech toxins back into the water for another reason which is in order to re-activate carbon particles (essentially remove impurities) requires industrial processes, temperatures over 1000 F and various chemical reactions. These impurities are not removed that easily.

 

I didn't know that either, do you have a link explaining the science of it as I'd like to learn more?
I might even use it if I understood the science behind it, never to old to learn

 

Just to clarify, I change my carbon filter regularly and am not promoting not changing filters on a regular basis.

So many of you have suggested removing the spent carbon filter but Duckweed won't be getting a new one for a while.
Doesn't the carbon filter house a lot of BB? And since the filter has been in there for a while, could removing it possibly greatly reduce the nitrification process?

 

You can just cut the cartridge open and dump the carbon. It's kind of a pain because the carbon doesn't want to move but once you get it out you can stuff tje cartridge back up with biomedia or more fresh carbon.

Carbon itself doesn't house much BB. It's mostly on biomedia and sponges. Coradee - There is a link on FL about it somewhere and I do have some links at home. I will check for it this evening.

 

Thank you, I'll do a search on here for that link

 

I found this from 2012 which is basically what PI said.
No disrespect to the author but it's just that they know someone who knows someone who's a chemist who said this about carbon, for something like this I'd like to read the science that proves it & understand it
https://www.fishlore.com/aquariumfi...ted-carbon-effectiveness-and-leaching.116152/

 

I have more links at home for it. I can dig them up this evening.

 

It looks like the information may be dated, and I am having trouble finding more current info in agreement (but can't find any in disagreement either) so I apologize. It isn't incorrect, but as has been previously stated, the conditions that prompt this exchange are not likely to occur inside an aquarium.

This was something we had discussed at length when u was in a chem lab in college. I will look into it more extensively and try to find a better explanation to satisfy my own curiosity!

 

Thanks for looking, if you do find something more recent & conclusive I'd be very interested in reading it

 

I will, for certain, keep you posted. From what I know about receptor sites, in any organic material (including the human body), binding affinity plays an important role. I'm going to find the answer for you all now, and myself haha.

 

Haha you sound like me, once I get a bee in my bonnet about something I don't let go until I've resolved it

 

Wow, this exploded.
Yeah, I don't know much about activated carbon, the only reason I have it is because it came with the tank. So I'm not sure what to do now. I think I'll just leave it in tonight, and research it tomorrow.
Thank you.

 

Well, the simple truth is that it's not doing anything good for your tank right now, being so old. We were just going back and forth on whether it leeches anything back into the tank but I think we're all in agreement that it's no longer working the way it should haha. I would suggest you cut open the cartridge, dump the carbon, and stuff it back up with either more carbon or biological media

 

My understanding is that anything adsorbed (bound to the surface, not the same as absorbed) cannot leach back into the water without a trigger that is unlikely to ever occur. The example I've seen presented most often as such a trigger would be a drastic change in pH, but it would be so drastic a change that leaching meds or impurities back into the water would not matter because all the fish would already be in trouble anyway. Naturally activated carbon should never have a problem with leaching. At least that is how I understand it.
Chemically activated carbon, on the other hand, can leach the chemicals - usually phosphate - into the water. I've got a very detailed story about this in an old TFH that I wish I could upload here. There's even carbon that is derived from coconuts of all things, which will also leach back into the water.

 

IMO, the main concern with leaving carbon in for a real long time, is it seems to clump up and can start to block the water flow thru the filter.

So while using or not using it is no big deal (just persoanl preference) using it, but not changing it can be problematic.

 

According to this opinion Activated carbon can leech phosphates into your tank

 

You brought up a good point Jomolager, however this only applies to some lower quality carbon filters and they will leech phosphates no matter what.

There are 2 methods used to activate carbon, physically and chemically. Carbon filters that are chemically activated and use phosphoric acid in the process will leech phosphates. So, def buy products that say 'phosphate free'.

I thought this link about carbon filters was very informative and even gives a rating to various carbon filters on the market.

 

Interesting article, although it is mostly for Saltwater tanks. FishLorians have bifurcated opinion on carbon. Some, especially those who have NO live plants in their tanks, use it religiously, others just as religiously don't. I leave it at that