Seachem Matrix - Nitrates?

[BradN88]

Hi everyone, I have a fluval 13.5 gallon nano reef....

For filtration, my water flow goes through a couple of blue/white pads.... then through chemi-pure blue and seachem purigen. In the middle chamber I have seachem matrix before the water is heated and returned to the tank.

I've heard from a few people that the seachem matrix is a nitrate factory and is not needed in a system like mine.

It's been a while since I've run a reef tank so I'm looking for some advice here.

Thanks in advance.

 

[vetteguy53081]

I agree that removing matrix may help. Chemipure is sufficient

 

[Covett03]

Any updates? I pretty much run the same and wondering why my nitrates are sitting at 6-9ppm. Did you remove the matrix? I thought matrix was bio for bacteria to help remove the big 3 (ammonia,nitrite,nitrate)

 

[ariellemermaid]

Any updates? I pretty much run the same and wondering why my nitrates are sitting at 6-9ppm. Did you remove the matrix? I thought matrix was bio for bacteria to help remove the big 3 (ammonia,nitrite,nitrate)

To remove nitrates you need anaerobic conditions for anaerobic bacteria. Matrix provides good surface area for bacteria, but if it’s in a high flow place you’re not going to get there. You’ll have more anaerobic bacteria at the bottom of your sand bed. As for ammonia and nitrites, sure, those bacteria will grow on it. Does it add that much to a well cycled tank with a lot of porous live rock and sand? Honestly, probably not. I still have some in my systems from when they were new, but not because I think it’s needed anymore. What it is super useful to me for is to rapid cycle my fish QT tank.

Also I wouldn’t stress about nitrates <10 in any way. Sure lots of people run near zero but some very successful 30 year old tanks run 50. If your corals are happy and your tank is doing well, there’s nothing to do about that. The biggest nitrate sink in my 20 gallon coral invert QT tank with an HOB is the Xenia that took over some of the rocks. I used to run about 20 between weekly water changes; now I’m <5 with minimal water changes.

Edit: also not sure about the nitrate factory thing, haven’t heard that. It doesn’t make a ton of sense to me. Places that trap debris to decompose will be “nitrate factories” like sponges. But matrix? I’m sure it traps some and I rinse my filter elements in WC water and get a lot of debris if I go a few months. But I think most of it is from sponges and the bag the matrix itself is in. If the matrix was free floating…I mean, matrix is just little pieces of very porous rock. Is your live rock a nitrate factory?

 

[Randy Holmes-Farley]

Edit: also not sure about the nitrate factory thing, haven’t heard that. It doesn’t make a ton of sense to me. Places that trap debris to decompose will be “nitrate factories” like sponges. But matrix? I’m sure it traps some and I rinse my filter elements in WC water and get a lot of debris if I go a few months. But I think most of it is from sponges and the bag the matrix itself is in. If the matrix was free floating…I mean, matrix is just little pieces of very porous rock. Is your live rock a nitrate factory?

I too am not generally too worried about nitrate factories, but I will clarify a way that a material can be a nitrate factory in a way you do not include. It could be for a nonporous surface, or a very porous material, neither of which attain anoxic regions.

Nitrate in the Reef Aquarium - REEFEDITION

Nitrate is an ion that has long dogged aquarists. It is typically formed in aquaria through the digestion of foods, and in many aquaria it builds up and can be difficult to keep at natural levels. In the past, many aquarists performed water changes with nitrate reduction as one of the primary...

www.reefedition.com

5. Filters Designed To Facilitate The Nitrogen Cycle.

Filters such as trickle filters using traditional bioballs do a fine job of processing ammonia to nitrite to nitrate, but do nothing with the nitrate. It is often non-intuitive to many aquarists, but removing such a filter altogether may actually help reduce nitrate. Consequently, slowly removing them and allowing more of the nitrogen processing to take place on and in the live rock and sand can be beneficial.

It is not that any less nitrate is produced when such a filter is removed, it is a question of what happens to the nitrate after it is produced. When nitrate is produced on the surface of impermeable media such as bioballs, it mixes into the entire water column, and then has to find its way, by diffusion, to the places where it may be reduced (inside of live rock and sand, for instance).

If it is produced on the surface of live rock or sand, then the local concentration of nitrate is higher there than in the first case above, and it is more likely to diffuse into the rock and sand to be reduced to N2.

In a reef aquarium with adequate live rock, there is little use for a trickle filter, so in general they can be safely removed.

 

[ariellemermaid]

I too am not generally too worried about nitrate factories, but I will clarify a way that a material can be a nitrate factory in a way you do not include. It could be for a nonporous surface, or a very porous material, neither of which attain anoxic regions.

Nitrate in the Reef Aquarium - REEFEDITION

Nitrate is an ion that has long dogged aquarists. It is typically formed in aquaria through the digestion of foods, and in many aquaria it builds up and can be difficult to keep at natural levels. In the past, many aquarists performed water changes with nitrate reduction as one of the primary...

www.reefedition.com

5. Filters Designed To Facilitate The Nitrogen Cycle.

Filters such as trickle filters using traditional bioballs do a fine job of processing ammonia to nitrite to nitrate, but do nothing with the nitrate. It is often non-intuitive to many aquarists, but removing such a filter altogether may actually help reduce nitrate. Consequently, slowly removing them and allowing more of the nitrogen processing to take place on and in the live rock and sand can be beneficial.

It is not that any less nitrate is produced when such a filter is removed, it is a question of what happens to the nitrate after it is produced. When nitrate is produced on the surface of impermeable media such as bioballs, it mixes into the entire water column, and then has to find its way, by diffusion, to the places where it may be reduced (inside of live rock and sand, for instance).

If it is produced on the surface of live rock or sand, then the local concentration of nitrate is higher there than in the first case above, and it is more likely to diffuse into the rock and sand to be reduced to N2.

In a reef aquarium with adequate live rock, there is little use for a trickle filter, so in general they can be safely removed.

Interesting food for thought. I guess the part of the argument I’m having a hard time with revolves around the idea that where the nitrate is produced matters in a high flow reef system where the water is turned over many times per hour. Nitrate produced in rock and sand mixes with the water column all the same by both flow and simple diffusion from high concentration to low concentration. For this argument to be true, it would have to be shown that a water sample from a lower flow area has a higher concentration of nitrate than the water generally. I have a hard time believing this could be true in tank of water with no semi-permeable membrane or structures.

Anaerobic bacteria flourish in areas with lower oxygenation, but that doesn’t mean that simple diffusion of solutes in a solution isn’t still taking place relatively homogeneously, relatively quickly. Especially when the flow just next to those areas is high, quickly mixing lower concentrations with higher ones to facilitate rapid diffusion.

However I’m here to learn just like everyone else! I think we can both take issue with the term “nitrate factory” though. What we’re talking about here is WHERE the nitrates are produced, not IF. A “nitrate factory” is referred to in a situation where nitrates are being produced where they shouldn’t be such as a filter sock or sponge with decaying material that should be removed rather than allowed to decay and produce ammonia and eventually nitrate.

 

[Randy Holmes-Farley]

Interesting food for thought. I guess the part of the argument I’m having a hard time with revolves around the idea that where the nitrate is produced matters in a high flow reef system where the water is turned over many times per hour. Nitrate produced in rock and sand mixes with the water column all the same by both flow and simple diffusion from high concentration to low concentration. For this argument to be true, it would have to be shown that a water sample from a lower flow area has a higher concentration of nitrate than the water generally. I have a hard time believing this could be true in tank of water with no semi-permeable membrane or structures.

Anaerobic bacteria flourish in areas with lower oxygenation, but that doesn’t mean that simple diffusion of solutes in a solution isn’t still taking place relatively homogeneously, relatively quickly. Especially when the flow just next to those areas is high, quickly mixing lower concentrations with higher ones to facilitate rapid diffusion.

However I’m here to learn just like everyone else! I think we can both take issue with the term “nitrate factory” though. What we’re talking about here is WHERE the nitrates are produced, not IF. A “nitrate factory” is referred to in a situation where nitrates are being produced where they shouldn’t be such as a filter sock or sponge with decaying material that should be removed rather than allowed to decay and produce ammonia and eventually nitrate.

There no evidence on whether the reduction in nitrate that folks see on removing bioballs relates to detritus accumulation (which theory only works if it is otherwise removed from the system) or the theory I suggested, or a combination of the two.