"nitrate Factories"

xxBarneyxx

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I see it all the time on marine forums. "Don't use Bio media/canister filter/carbon/filter floss/any number of other things that aren't liverock because they are nitrate factories and you will end up with really high nitrates".

What I want to know is if anyone has actually seen and properly conducted studies to prove this is true and if im just missing something completely.

The two reasons I have seen for "Nitrate Factories" are:
1) It processes the ammonia and nitrite "too fast" but there is nothing then to remove the nitrate.
2) You will get a debris build up in it.

Now for reason 1, surely getting rid of the ammonia and nitrite as quickly as possible is a good thing? I certainly would prefer nitrate to either ammonia or nitrite.

Now lets assume you have two tanks identical in every way, both have LR as the main form of filtration (and nitrate processing). Tank A has a canister filter and Tank B does not.

Now lets assume the ammonia in Tank A is being processed "quicker". This would mean that there is an initial spike in nitrate but the ammonia and nitrite are gone much quicker. Assuming both tank A and B have the same amount of ammonia going in they are going to have the same amount of nitrate coming out. The only difference being is that Tank B will have less nitrate at any given time (but if there is less nitrate it will mean there is more ammonia and nitrite).

Basically what I'm saying is that with or without an external filter there is the same amount of nitrate and if you use LR then you either have the capacity to process this nitrate or you don't (regardless as to if you have a filter or not).

Now with regards to the detris being collected. If you are getting debris build up in a filter then it means that you have detris in your tank. If it is in the tank its going to break down and rot regardless of if its stuck in your filter media or if its floating around behind your liverock. The end result will be the same but at least if its stuck in a filter its easier to get to.

There may be something I'm missing here so if there is please let me know.
 
sponges are great as long as you wash them out weekly in tapwater to kill the bacteria. i see the point of your post but dont know the answer ill look into it and get back to you
 
me again lol

the reason sponges in an external filter are classed as nitrate factories is that the bacteria is present to get you to the stage of nitrate BUT....

the water flowing through the filter is oxygenated and the bacteria to convert nitrates to nitrogen gas to be dispersed from the aquarium are anaerobic and they will be able to live in a dsb and inside live rock as these are areas both lacking in oxygen.

so if you are for running sponges make sure they are washed at least once a week but if you have enough live rock you have no need to have a canister filter running other than maybe for po4 remover and carbon

hope that helped mate

owlbassboy
 
too much live rock/not enough flow can also be a nitrate factory. It all about flow and build up of detritus IMO.

if you have good flow through your rock/bio balls/filter media, and no build up of detritus i see no reason why these would become nitrate factories.

I run my system with a sheet of filter floss in the first chamber of my sump. It removes the larger particulates from my system, and as long as i change this media every week i get no build up of nitrates.

most people (me included) say to ditch most filter media (especially in external filters) as its a real pain having to take apart an external every week and clean/throw away the media.
 
me again lol

the reason sponges in an external filter are classed as nitrate factories is that the bacteria is present to get you to the stage of nitrate BUT....

the water flowing through the filter is oxygenated and the bacteria to convert nitrates to nitrogen gas to be dispersed from the aquarium are anaerobic and they will be able to live in a dsb and inside live rock as these are areas both lacking in oxygen.

so if you are for running sponges make sure they are washed at least once a week but if you have enough live rock you have no need to have a canister filter running other than maybe for po4 remover and carbon

hope that helped mate

owlbassboy

Thats kind of my point. If you have enough liverock to remove the nitrate then it doesn't matter if the first two stages are done via the liverock or via bio-media the liverock/DSB, etc will still process the nitrate.

If you are running with a canister filter only then of course you will get a nitrate build up. However nobody runs a reef system with only a canister filter anyway and using any kind of filter media always tends to get called a "nitrate factory" (from sponges to activated carbon).

Yes if you have Liverock and a decent amount of flow then using bio-media in the sump or a canister filter is not really needed (though I now keep a bag of bio media in my sump for emergency use in a QT if I ever need it, I don't use anything else though).

The point I'm trying to get at though is that if you do use additional media it wont actually make any difference to the nitrate levels in the tank in the long run (when used in conjunction with the common berlin method) and that saying they are nitrate factories is wrong.
 
Clayton from Reefworks talks about this in his thread on UR about the tank he set up for SPS. He used Bioballs in the sump and said and explained why they would not be Nitrate factories. Its the one that can be seen on Reefworks website and was showcased as a series when he set it up in Ultra Marine Magazine.
 
Hey xxbarneyxxx
I couldn't agree more mate.
I have seen it and herd all the same garbage that you have.
There are so many trendy opinons,based on stupid mistakes,its rediculas.
I have kept marines for around thirty years and experimented with near on everything and this nitrate factory bull is quite funny if it wasn't so stupid.
All mebia with avaliable oxygen generates the slowest (to remove) part of the nitrite cycle.
How hard is that to understand,you just have a slow(clean)dead spot to convert it to nitrogen.
The clean bit is where it has always fallen down and created a fantasy land of opinons.
Hey,lets not say to much or there will be less fish bought.
 
I think some of this "myth" generates from laziness in upkeep. I know when I was keeping freshwater, I wouldn't meticulously change media when it should have been. With hobs and canisters, since they do work so efficiently, I think people are inclined to lose track of when sponges, carbon and biomedia should be cleaned/replaced. Without proper care, i could see these producing alot of nitrate.

I also think most people with hobs/canisters are not keeping reef tanks, so they might not have proper flow or enough live rock. I liken this to a freshwater system which is why there are more waterchanges required for freshwater systems.

In a FO with a hob/canister, wouldn't you need to change water more frequently? With freshwater, I was changing like 10-15% weekly and that's PITA.

I am curious as to how many people are keeping reef tanks with a hob/canister.
 
Adding a deep sand bed to either your sump or display tank will allow for anaerobic bateria to culture and help break any nitrate into it's component elements, thus dropping nitrates drastically
 
To be honest I cant think of anyone that uses a standard setup canister filter or bio-media on a reef tank, think this is due to a combination of it not being needed when you have LR and that "everyone knows they are nitrate factories :) ".

I know quite a few people that use them for chemical filtration though or fill it with LR rubble as a cryptic fuge.
 
If you never let any thing get to your deep sand bed they work great permenantly.

It's the same with all filtering,prefilter it and it will function for ever and a day,near on no one does this properly.

If you have a 5 mill size piece of coral in your water it becomes bio active at nitrites,if you have a 20 mill piece of coral,the outside of it and in a little becomes bio active to convert nitrites and deep in it will develope some nitrate converting as the oxygen is used up by the aerobic communities.

It is very simple,you grow anything in a deep sand bed or similar or let rubbish of any amount get to it,sooner or later it will begin to fail,how much,who knows,but it will fail to function at it's maximum level,no doubt,than you have a poluter and a partial converter,not just a converter.

It is a thing that only time can prove and i have had a lot of time to prove this,most people give up after a few years of not quite doing it right,it's not all bad,some one than gets some cheap gear for there new hobby.

You can not have a similar functioning part of the ocean with out,very,very careful prefiltering.

Out there each reef of a kilometre has a hundred kilometres of plankton to clean the water before the next reef recieves it.

Did every one forget or was never taught the oldest and most important part of aquarium keeping,parts per million.
 
Here's my take on this whole thing Barney, I'm gonna try and pull together a bunch of things said here that I agree with.

First off, everyone needs to remember that our tanks are EXTREMELY nutrient dense compared to the ocean, and are devoid of the ocean's primary nitrate filtration known as phytoplankton. In that situation, our systems become bacterial driven out of necessity which has consequences of its own.

As mentioned, bacteria are REALLY good at converting ammonia to nitrate. They also will live on most any surface, including that of LR, glass, plastic, sand, and mechanical media/sponges if they are so used. Even if you have a tank with sand only and plastic decorations, so long as there's decent flow, you can grow the bacteria necessary for the nitrogen cycle. It may take a little more time, but it can be done, so lets get off this train that the bacteria that process NH4---->NO2 need specific substrates to live on, they really dont, they just need water movement.

However, the rate limiting step in all of this is the decomposition of waste. In an estabilished system, NH4---->NO2 is FAST, so fast that as soon as ammonia is available its gone. So it's how fast that waste decomposes to NH4 (and PO4, don't forget that) that limits the production of NO2. This also provides us for 3 ways to intercept the cycle right here. First is through foam fractionation (aka protein skimmers) to remove larger complex organic molecules BEFORE they decompose to become NH4/PO4. However, estimates are that only ~30-40% of dissolved organics are actually ABLE to be removed by foam fractionation, the rest can decompose into NH4/PO4 and we can't do much about those, so they end up breaking down.

Now, our second method for intercepting the decomposition of dead matter or fish waste is biological. Encouraging BASIC filter feeding sponges, tunicates, and others via cryptic zones has more application than you think. Anyone ever turned over rocks that were in an established tank for a long period of time and looked at what grows under there? All kinds of sponges and funky lookin creatures. These guys consume the detritus and dead matter BEFORE it becomes NH4/PO4. As you pointed out Barney, that's the major benefit of using canister filters as cryptic zones. All these organisms it encourages intercept the cycle and we "see" less NO2

Thirdly, we can HOPE that we encourage a mature sand bed full of organisms who also eat detritus and the like. However, this may not be possible based on the biodiversity (or lack thereof) of the system. There are organisms that will consume detritus that falls in the sand bed, but they are NOT sand sifting gobies and/or starfish. Those two types EAT the little tiny micro invertebrates that would otherwise process detritus. And thus are counter productive.

Now here's my issue with Canister filters. You've got a brand new reefkeeper coming over from the freshwater side. Sure, he/she has become familiar with keeping freshwater fish and even successful at it. Yet tbh, it's not much of a challenge. Thump a filter in there, cycle the tank, don't overstock it, waterchange on a semi-regular basis and voila, instant easy to care for fishtank. Now they come over here and think similar things apply yet they don't account for the extreme biodiversity difference here. So they follow some advice, and get some LR but still want to use their canister filter cause they've been taught (mistakenly so) that that's the only way to encourage bacteria to grow. So they have the canister with biomedia in it with LR, the tank "cycles" quickly and they think, "great, lets toss some fish in," not realizing for a moment that there's still a million other biological processes trying to find equillibria in their tiny seawater box. The fish start pooping and the canister filter dutifully gobbles up that poop and traps it in the filter media the fishkeeper has. Little do they know, they've just prevented that detritus from having a chance to be consumed by live sponges, tunicates, worms, etc and thus forced it to decompose naturally to NH4/PO4.

Now full decomposition of waste does take significant time but the aquarist is NOT used to regularly cleaning thier canister filter so they leave it be. Nitrates and phosphates slowly build up in the water column and who comes to the rescue again? Bacteria... but this time it's cyanobacteria. And I see the millions of posts about "red slime" and "nasty algae", nobody knowing where in the world it may have come from... Never considering the stuff probably hitched in on your LR and was just waiting for the right conditions to thrive, now supplied by decomposing detritus. So before higher organisms like corals, calcerous algae, or even algaes in refugiums can act, the display tank is over-run by nuisance algae and the aquarist still has not cleaned their canister filter.

Ultimately it's lazy practices that encourage the creation of NO2/PO4 and why I don't reccomend people use canister filters. Now, if you cleaned the thing weekly, thus removing all that waste from decomposing, you've got a great method for intercepting the decomposition cycle, but whose OCD enough to do that? Bioballs are a different matter in my oppinion because depending on how they are used, they do not trap as much detritus as sponge and mechanical media do and thus do not disrupt the ability of natural detritovores. If it were up to me, I'd still prefer new aquarists to not use canister filters cause it FORCES them to learn the biology/ecology of their tiny seawater boxes, often times through painful experience. People don't learn from what others write, cause if they did, I'd never hear questions of why my tank is overrun by cyanobacteria. People learn from experience and that experience is faster/easier to explain when they are not monkeying with the biology with man-made solutions requiring OCD level attention.

Heck, I've been doing this for years and I still struggle to clean the inlet strainer on my pump and the sleeve of my UV unit. Despite the fact that it takes me maybe 15 minutes to do it all, I still don't want to.
 
If you have the room this style keeps nitrates at zero always and the algae in the tank keeps the phosphates a no show.
bio-filter-.jpg
 
Reall neat idea pkc, I like it. IME, a well-lit refugium does the job well too :)
 

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