What’s Your Beef With Activated Carbon?

Discussion in 'Filters and Filtration' started by AquaticJ, Apr 20, 2019.

  1. AquaticJFishlore VIPMember

    Id like to hear everyone’s thoughts on the use of carbon in their tanks. There’s this trend that I see everyone following, carbon is dumb and only is good for removing medication.

    Now I will say, a lot of my tanks don’t use carbon, but some do. I get that it’s not necessary, but to poke holes in that argument, you can cycle a tank without any media in your filter. They just grow in and on the filters surface. I also understand it costs money, but again to poke holes in this, you can make that argument for a lot of things we use. For example, buying Seachem Matrix costs a fortune when you can get a 5 lbs bag of lava rock for $10 at many hardware stores. Or heck, if money is a concern, why not just use all sponge filters?
  2. Pat93Valued MemberMember

    I do use all sponge filters, if the power goes out I just plug in my battery powered pump and my tanks stay filtrated.

    The real argument against carbon for me is that it doesn’t filter ammonia nitrite or nitrate in any way other then when good bacteria grows on its massive surface areas

    Another thing is for you really to get the benefit of the carbon filtration you(allegedly) need to have your water go through at least 100 micron filtration before it ever hits the carbon otherwise your carbon gets gunked up with big particles and doesn’t filter any of the small stuff from the water it’s advertised to.

    I’ve heard but can’t confirm that It also filters out some of the stuff people with planted tanks are putting in to help their plants grow, I’ve never had that problem my own carbon filtered planted tank, though I did eventually take the carbon out anyway

    People buy the media instead because the surface area on a jillion bio balls in your hang on back gives you a way higher stocking capacity (more surface area=more bacteria=more ammonia processing power) then the one bag of carbon that came with it. And you don’t ever have to change bio balls you just rinse in the aquarium water from your water change and put them back if they get crazy dirty

    Also note, Seachem paraguard has a disinfectant in it that is not removed by carbon and supposedly “dissipates” after 24 hours so their are plenty of medicines I’m sure would go right through carbon

    In closing, use whatever works for you, your fish, and your wallet. I’d rather spend the $ on fish meds or sponge filters than carbon but I do usually use the little bag that comes with the hang on back and I’ll even take the carbon out of them and make my own diy carbon filters

    Oh and I almost forgot my carbon filtered tank seemed to have less of an algae problem than my non carbon filtered tanks.so that could be and argument for carbon
    But I keep corydoras and snails so I never really have algae anyway.

  3. endlercollectorFishlore VIPMember

    I actually think activated carbon is wonderful stuff. So simple, based on an ancient technique, yet incredibly useful. There are fish who are heavy polluters, and I would use activated carbon specifically for them. I have used it a lot in the past, but since my Endlers don't produce much waste in comparison, I get by with dirted tanks, tons of plants, HOB, and sponge filters. But if I had goldfish or cichlids, I would definitely use it.

    And here's a cool article about the production of activated carbon:  

  4. david1978Fishlore LegendMember

    I quit using it years ago. Did I notice any difference? Not really. Does it have it uses? Yep.

  5. SkavatarWell Known MemberMember

    i've not heard that "carbon is dumb" only that is not a "must have" item that "needs to be used all the time"

    the two main uses are for removing odors and medication.

    you do realize that the more porous your media is, the more BB it can house. so a filter without media can't support as many fish (bioload) vs the same filter with media in it.

    same argument with Matrix (pumice), which has twice the porosity of lava rock (scoria).

    fish keeping in general costs money.
  6. coralbanditWell Known MemberMember

    It does very little in the aquarium that water changes don't do better .
    Now if you have issues with your source water then carbon may be very helpful but at that point in reality I would hope you looked to use better carbon then is sold through the pet industry .Carbon in situations where it could remove something will be used up in days .Often as mentioned it becomes coated with detritus so inside of each pellet is not really used at all .There are not only different grades of carbon but different types , like made from coconuts ...The stuff in filter cartridges /pouches is garbage from day 1..
    I would think if someone wanted to use carbon for a couple days a couple times a month it might help some ,but if you are doing water changes really ?
    And if your carbon is in your filter cartridge / pouch forget about it .
    My beef well not mine I don't use any but many want to know how about HLLE ? Carbon has been linked to it .
  7. david1978Fishlore LegendMember

    Pfffft. Costs money. Other then the tanks, equipment, fish, decor, food eh were was I going with this?
  8. AquaticJFishlore VIPMember

    I think the whole porosity argument is a bit funny. It’s just a marketing ploy. This very recent study has shown that scoria was more efficient overall, specifically with nitrite and nitrate removal, whereas pumice was shown to be better at ammonia removal. This is not to say that neither have the ability, the scoria was just faster at achieving it.

    The porosity of pretty much any kind of bio media, sponge, etc is more than capable of harboring enough bacteria. And if it’s not, you have WAY too many fish.

    I’m not sure I buy the HITH thing, they only studied saltwater Tangs, not any other saltwater or freshwater fish. There also hasn’t been enough replication on that, in my opinion. Tangs are crazy vulnerable to HITH from the get go.

    You’re absolutely right about the carbon filling up, but I think using it correctly is half the battle. You should put media before it to catch large debris like detritus. I’ve also heard whispers that carbon will remove growth inhibiting pheromones, as they are organic.
  9. coralbanditWell Known MemberMember

    While this may be true ,water changes do the same ? Yes ? With other benefits and less questionable side effects ? Yes ? :woot:
  10. CichlidudeWell Known MemberMember

    It appears the Internet has been lying about lava rock.

    Lava Rock:

    The truth about Lava Rock is to  .

    Lava rock is another bio media that bacteria can colonize on. By looking casually at a lava rock, it actually looks like a sponge. if it has the structure of a sponge, it would have been a much better bio media. However, it is not. It just looks like it and the similarity stops there.

    Lava rocks have many holes (air pockets) throughout the rock but they are not connected and does not allow water to flow through them. As a result, water does not flow through lava rock. Water that flows pass lava rocks just travel around them.
    Last edited: Apr 20, 2019
  11. SkavatarWell Known MemberMember

    I skimmed through the article, its core study is the adsorption capabilities of scoria and pumice. No where did it mention the nitrification or denitrification processes that we fish keepers need. We use them as bio media for growing bacteria.
    The majority of fish keepers who use Matrix, Biohome, or other high porosity biomedia use them to grow anaerobic bacteria in the core of the media.
  12. grump299Well Known MemberMember

    Well the long and short is everyone has an opinion on activated carbon and no one is wrong it is what works for you. Myself I don’t like it because it needs to be changed every 3-4 weeks and it’s a pain to open my canisters that often now if I need it I will use it.
  13. kallililly1973Well Known MemberMember

    I don't use it either in any of my 6 planted tanks. But that's all i'm going to say about this subject. I like all the opinions about the use of or lack of use of carbon. The winner is the OP that came up with this question. Very informative thread!
  14. Michael.j.gomezValued MemberMember

    Hello, I stopped using carbon in my tanks for about 1.5+yrs. My reasons are that if a tank is properly maintained there will be no offending odor to remove & if there is a fishy odor then something is out of whack that needs to be attended to but masked by the carbon.
    I've also read that sometimes carbon releases the contamination it has collected which causes water problems & even death in tank. Hope this helps!
  15. scarfaceFishlore VIPMember

    I did notice a significant difference in water clarity when using carbon and not using it, but I'm talking a large bag of it for only a 3g aquarium. I have no beef with carbon. I neither recommend nor dissuade anyone, in regards to it. However, if there is one main reason I don't use carbon any longer is there are just too many contradictions about it and no clear answers. Is it harmful to fish? Does it really potentially cause HITH disease? What about ferts? Does it remove a significant amount? Lots of opinions. Who's right? I don't know, so I'm not using it. But I'm not stopping anyone else.
  16. AquaticJFishlore VIPMember

    Here’s the chart, a scientific study, supporting my claim. You have to go far down.

    I really hope you guys read the study and not just skim it, it’s all there. It even talks about the structure of each. If lava rock is so bad, according to fishyou.com which is a website I’ve never heard of, then how do they explain this study with numbers, figures, data, etc? Again, please actually read the study or else this isn’t worth debating over. Also, with a traditional filter, it doesn’t matter how great your media is, you’re not harboring denitrifying bacteria. And I know for a fact @Cichlidude knows that.

    And I appreciate everyone else’s input!

    Attached Files:

  17. toosieFishlore VIPMember

    Ummmm...its a short chart.

    Edit: Ok, I see, it's from the link in your post above. :cool:

    From what I gather from reading your previous link, as well as from reading the one I'll link to below, it sounds to me...and I could be wrong...that the effect scoria has on nitrogen products isn't due to providing surface area for beneficial bacteria to colonize but is due more to "static absorption" and "van der Waals forces", and although ion exchange was explored, no ion exchange was found.

    I haven't read up more on pumice so I'm not sure if it works the same way or not. But if part of the debate is on whether or not lava rock is a good biomedia, then determining how it removes nitrogen products would be important. But so far I haven't read anything that tells me it's a good biomedia. But like zeolite's ability to remove ammonia (through ion exchange, but also not a good biomedia) lava rock may have value in nitrogen removal...pH may play a role? and there also sounds like there may be some inhibiting factors ("interfering ions"), so... it doesn't all sound cut and dry. And I suspect the environment in which this media is used in these treatment plants, is controlled in areas such as pH and interfering ions in order to obtain the desired effects. Something we can't control to that degree in our aquariums with live fish, invertebrates and plants.

    I think various media hold value such as; activated carbon, zeolite, and possibly, lava rock, among others...and can be useful tools when employed under appropriate circumstances, but I don't think that means they should necessarily take up full time residence in our filtration systems. And understanding how they function, I think, could be important, in order to decide if they are right for you. But what media to use and why, I think, are a matter of personal preference.

    Last edited: Apr 21, 2019
  18. AquaticJFishlore VIPMember

    “These mechanisms are straining, sedimentation, impaction, interception, adhesion, adsorption, flocculation and biological degradation especially for organic removals on the top of the filter medium”.

    I use lava rock in some tanks and pumice in others, and they both work the same, all my tanks are cycled.
  19. grump299Well Known MemberMember

    Agreed I also use lava rock in both my canisters not as primary bio media I use it just before my primary media is matrix yes it expensive but it only a one time buy.
  20. toosieFishlore VIPMember

    It does not say that lava rock does all of the above. They are saying that the above are all methods used to filter and treat the waste water. And they go on to explore how lava rock can help and the processes it uses. Don't give lava rock more credit than it is due.
    Last edited: Apr 21, 2019