# Seachem Matrix



## Gary Nelson (13 Sep 2013)

Hi, is anyone using this in the filters as bio media? I keep reading it removes NO3?


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## Alastair (13 Sep 2013)

Hi gary, I used to use this on my high tech tank a couple of years ago. Worked brilliantly and didnt notice any negative effect 

Sent from my GT-I9505 using Tapatalk 2


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## dw1305 (13 Sep 2013)

Hi all,


Gary Nelson said:


> I keep reading it removes NO3?


 It is another one of those advertising blurbs that may be true in a specific set of circumstances, but "deeply sceptical" doesn't even cover it for me. This subject is covered pretty fully here: <Alfagrog for reducing Nitrates? | UK Aquatic Plant Society>

If we assume that you can have both aerobic and anaerobic filtration in the filter, it depends upon the flow through the filter and how often you clean the media. The idea with "Seachem Matrix" is that the inner pores are anaerobic and within these de-nitrification of NO3 to N2 gas occurs, in the larger macro-pores aerobic bacteria convert NH3 - NO2 - NO3. But, how are you meant to get the flow at a level where you get the mix of aerobic/anaerobic? if all your filter material becomes anaerobic, you lose all your biological filtration and toxic ammonia levels build up.

This is from <Filter maintenance. How regular do you do it? | UK Aquatic Plant Society>, and for me it really summarises biological filtration. 





dw1305 said:


> What-ever else people tell you on other forums etc, you just need to remember that *biological filtration is all about oxygen*. The key parameter for scientists who are interested in water quality (at the Environment Agency etc) is BOD (Biochemical Oxygen Demand). What this quantifies is the total amount of dissolved oxygen that would be used by the biological (bio-load) and chemical processes within that water body. The higher the BOD is, the more polluted the water is, and the more oxygen we have to supply.


 The whole thread is worth reading.

cheers Darrel


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## Christian Walker (13 Sep 2013)

I would think that the variance in flow comes from the fact that on the outer part of the media, flow is relatively fast as its essentially flowing "over' the media.  This is the flow most people can understand as it is caused by the water being pumped by the filter.  I am of the opinion that in certain media types, there are inner pores and channels and that flow in this is very much reduced (the bulk of the flow running over the media as already mentioned). The action of the water flowing over the media is enough to cause movement within the media as well, thus allowing for aerobic and anaerobic filtration to occur.  This is pretty much the same theory as LIVE ROCK in a marine aquarium, and this is a commonly accepted process among marine fishkeepers.  I see no reason why it cannot work in a similar way in a freshwater setup.  The only difference is that in the marine tank the flow is usually caused by water flowing over the rock in the tank (remember, those boys often have up to 50x volume flow) or in the sump, as opposed to in a filter canister with a freshwater system.  Thats my take on it at least


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## Gary Nelson (14 Sep 2013)

Alastair said:


> Hi gary, I used to use this on my high tech tank a couple of years ago. Worked brilliantly and didnt notice any negative effect
> 
> Sent from my GT-I9505 using Tapatalk 2


 
Cheers Alastair, think I will get some and give it a go. 



dw1305 said:


> Hi all,
> It is another one of those advertising blurbs that may be true in a specific set of circumstances, but "deeply sceptical" doesn't even cover it for me. This subject is covered pretty fully here: <Alfagrog for reducing Nitrates? | UK Aquatic Plant Society>
> 
> If we assume that you can have both aerobic and anaerobic filtration in the filter, it depends upon the flow through the filter and how often you clean the media. The idea with "Seachem Matrix" is that the inner pores are anaerobic and within these de-nitrification of NO3 to N2 gas occurs, in the larger macro-pores aerobic bacteria convert NH3 - NO2 - NO3. But, how are you meant to get the flow at a level where you get the mix of aerobic/anaerobic? if all your filter material becomes anaerobic, you lose all your biological filtration and toxic ammonia levels build up.
> ...


 
Thanks for that Darrel, and the links you have given me are a very good and interesting read! I've just about got my head around it


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## ceg4048 (14 Sep 2013)

Gary Nelson said:


> Cheers Alastair, think I will get some and give it a go.


THE....MATRIX........HAS....YOU....NEO...

KNOCK......KNOCK.....


Cheers,


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