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Dr Timothy Hovanec's comments about Bacterial supplements

Im thinking that all that sludge we have in our media is creating a breeding ground for the Heterotrophic bacteria and as the Dr said causes the nitrification to slow or stall.

So if when we rinse out our media to create the flow we need how do we get rid of the sludge, but keep the good bacteria? Is it just a case of making sure our maintenance is less vigorous? so we dont wash the good away? Obviously our plants are more than ready to take up any slack created by rinsing until they recover?
 
Hi @Jaseon

You may find this helpful.:


I'm still grappling with some of the things the author says in the above.

JPC
Yeah it seems at odds with what Dr tim was talking about with the Heterotrophic bacteria which the article states 'This process creates bacteria free, crystal clear water which is important for fish health',

but a large presence of it might indicate that the filtration is becoming clogged with muck (organics) to the point where by it has a negative effect on the nitrifying bacteria?

Also

One of the best write-ups on this subject came from Swiss Tropicals, the supplier of Poret Foam. They said:

The brown filter sludge in a filter is for the most part alive and not simply waste. Removing this mud does more harm than good.

If a filter is going to be clogged at some point with this sludge which in turn produces more Heterotrophic bacteria (which we dont want) how do we navigate around that? Just simply good maintenance?

Maybe thats one way of running into high nitrite readings ie a blocked filter which in turn affects your nitrifying bacteria. Please tell me im right as i dont want to think about it any other way LOL.
 
I'm still grappling with some of the things the author says in the above.

If a filter is going to be clogged at some point with this sludge which in turn produces more Heterotrophic bacteria (which we dont want) how do we navigate around that? Just simply good maintenance?

Hi @Jaseon

Yup. That's why I can't get my head around the statement in the Aquarium Science comments.

JPC
 
Hi all,
If a filter is going to be clogged at some point with this sludge which in turn produces more Heterotrophic bacteria (which we dont want) how do we navigate around that? Just simply good maintenance?
Have a look at <"Extended Aeration">. If you have high oxygen levels <"most oxidisable material"> will be oxidised.
I'm still grappling with some of the things the author says in the above.
He is keeping fish at <"insane stocking rates">, he needs very efficient nitrification as he has no safety net and his filter is a <"single point of failure">. I think that is partially why he likes <"Kaldnes type media">, it can't clog.
If a filter is going to be clogged at some point with this sludge
Dr Stephan Tanner (of <"Swiss Tropicals">) is<"referring specifically to HMF filters">, things are <"slightly different with canister filters">. Even though we concentrate on microbial nitrification there are a <"whole suite of other organisms"> <"involved in the remediation of waste water">, many of which will occur in <"filter sponges etc">.

I think @Jaseon has been <"down the HMF route">?

In waste water treatment (and aquaculture) often there isn't a filter media as such, the bacteria, archaea, rotifers, protists etc <"clump together to form bioflocs">.
Are the revised names for the bacteria the same for fresh water? Its a bit of a surprise that the bacteria that are seen in the treatment of sewage are not the same ones that we commonly associate with our aquariums.
Yes, the <"past is a different country"> none of the bacteria that were thought to be essential for nitrification <"actually occur in aquarium filters">. You wouldn't know it from most Aquarium literature and forums, but the <"traditional linear view of cycling definitely isn't right">.

cheers Darrel
 
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Im not sure why that guy is used often as an example in the discussion as he represents the extreme end of what most of us are used to ie 'normal' community tanks with modest stocking levels. 6.2. Biofiltration

I suppose his stocking level is quite different than what most users here have. But if it works for him, it should work probably work for smaller bioloads as well.
I mean if you have hardly any fish in a giant planted tank almost any filtering will be enough.
His situation is not so different as say a watertreatment plant is compared to an aquarium, so I don't see why for example his research on filtermedia should be discounted.
 
Hi all,
His situation is not so different as say a water treatment plant is compared to an aquarium, so I don't see why for example his research on filtermedia should be discounted.
That is pretty much where I'm coming from.

I think there are <"valid criticisms of some of the content">, but one reason I've referenced his site is that it is <"one of the few resources"> that <"uses the scientific method"> and makes some attempt at replication etc.

I'll be honest, personally I think there are <"too many unknown unknowns"> to <"quantify exactly"> what makes an aquarium "successful", but <"you can use probability"> and <"scientific research in related fields"> to get a "best guess" about what is likely to work and what is <"snake oil">.

cheers Darrel
 
I suppose his stocking level is quite different than what most users here have. But if it works for him, it should work probably work for smaller bioloads as well.
I mean if you have hardly any fish in a giant planted tank almost any filtering will be enough.
His situation is not so different as say a watertreatment plant is compared to an aquarium, so I don't see why for example his research on filtermedia should be discounted.

Yeah I didn't think of it along those lines i just thought why muddy the waters when for me at least i felt i was starting to get somewhere, and understand it more. I thought the same thing with the water treatment analogy in as much it uses different bacteria than we see in the aquarium, but the process is the same so its still valid.
 
Yeah I didn't think of it along those lines i just thought why muddy the waters when for me at least i felt i was starting to get somewhere, and understand it more. I thought the same thing with the water treatment analogy in as much it uses different bacteria than we see in the aquarium, but the process is the same so its still valid.
Yeah, this is a topic where it sometimes feels like the more I read, the less I know. But like Darrel keeps saying, there isn't one way to go about it. There are many ways to have good filtration or to cycle a tank.
 
Hi all,
i just thought why muddy the waters when for me at least i felt i was starting to get somewhere, and understand it more.
For me the simple answer is just have plenty of plants, with some of them having access to <"atmospheric oxygen and CO2">. After that everything else <"is of lesser importance">.
Yeah, this is a topic where it sometimes feels like the more I read, the less I know. But like Darrel keeps saying, there isn't one way to go about it. There are many ways to have good filtration or to cycle a tank.
I really don't care how people get there, I want people to keep planted tanks because planted tanks just make fish keeping easier and more enjoyable.

If we (as a forum) can help people <"avoid getting ripped off">? I think in the long term that is <"better for everybody"> (including the vendors of filter media, test kits etc).

cheers Darrel
 
Hi all,

For me the simple answer is just have plenty of plants, with some of them having access to <"atmospheric oxygen and CO2">. After that everything else <"is of lesser importance">.

I really don't care how people get there, I want people to keep planted tanks because planted tanks just make fish keeping easier and more enjoyable.

If we (as a forum) can help people <"avoid getting ripped off">? I think in the long term that is <"better for everybody"> (including the vendors of filter media, test kits etc).

cheers Darrel
Well ive learned a lot since being here so im happy. I do like to know how it all works in general so any poking i do is just from wanting to know more, and not to disprove anything in general so its all good. Im certainly no fan boy when it comes to filters, and media etc, and if it makes sense to me ill go with that.
 
Since joing this forum its been a never ending days/weeks of reading material here. My 'watch' list grows everyday whe I check in and now its way longer than the internet bookmark list by a long shot.
I thought prior to arriving here I had a bit of a handle on water chemistery....... how wrong was that assumption. This is by far the best forum everev and thanks to all who contribute......
Dirk
 
Hi @Jaseon

I can't remember if Dr Hovanec mentions this - but nitrifying bacteria avoid light, particularly blue light and UV light. So, the place for them to reproduce and multiply is inside the typical filtration unit - be that a canister or simple sponge filter. Heterotrophic bacteria, on the other hand, are plentiful in the water column.

JPC
This is interesting and adds further merit to the idea of reducing the blue light spectrum to reduce risk of algae when starting up a new tank. Double the benefit.
 
"Ideally, the nitrifiers should neither be exposed to sunlight or room light of a color other than red (e.g., darkroom lighting). When grown as an attached biofilm, though, considerable shading provided by bacterial layering will shelter the lower organisms from stressful light. Hence, this recommendation against light exposure is somewhat conservative." Behavior and Physiology of Nitrifying Bacteria

Ammonia-oxidizing `nitritifiers' are sensitive to a region of the light spectrum known as near-shoulder' ultraviolet (Alleman, 1987)...For those `nitritifiers' affected by light, though, darkfield repair is possible, during which these bacteria rehabilitate over a period of hours in the presence of an available energy producing substrate.
Culture irradiance below 250 μmol m−2 s−1 did not show a significant effect on nitrification activity, while irradiance at 500 and 1250 μmol m−2 s−1 caused a decrease of 20 and 60% in the specific total ammonium nitrogen removal rates and a reduction of 26 and 71% in the specific NO3− production rates, respectively.
Light irradiation over 500 μmol/m2 s reduces bacterial nitrifying activity. Influence of light intensity on bacterial nitrifying activity in algal-bacterial photobioreactors and its implications for microalgae-based wastewater treatment

Correct me if I'm wrong, but isn't 500mm way more light than any of use? My low tech tank is at well under 40mm at the substrate (based on the light's mm rating at given height. I don't own a par meter)

What mm levels are high tech tanks using?
 
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"Ideally, the nitrifiers should neither be exposed to sunlight or room light of a color other than red (e.g., darkroom lighting). When grown as an attached biofilm, though, considerable shading provided by bacterial layering will shelter the lower organisms from stressful light. Hence, this recommendation against light exposure is somewhat conservative." Behavior and Physiology of Nitrifying Bacteria

Ammonia-oxidizing `nitritifiers' are sensitive to a region of the light spectrum known as near-shoulder' ultraviolet (Alleman, 1987)...For those `nitritifiers' affected by light, though, darkfield repair is possible, during which these bacteria rehabilitate over a period of hours in the presence of an available energy producing substrate.
Culture irradiance below 250 μmol m−2 s−1 did not show a significant effect on nitrification activity, while irradiance at 500 and 1250 μmol m−2 s−1 caused a decrease of 20 and 60% in the specific total ammonium nitrogen removal rates and a reduction of 26 and 71% in the specific NO3− production rates, respectively.
Light irradiation over 500 μmol/m2 s reduces bacterial nitrifying activity. Influence of light intensity on bacterial nitrifying activity in algal-bacterial photobioreactors and its implications for microalgae-based wastewater treatment

Correct me if I'm wrong, but isn't 500mm way more light than any of use? My low tech tank is at well under 40mm at the substrate (based on the light's mm rating at given height. I don't own a par meter)

What mm levels are high tech tanks using?
That depends where and how deep you measure the radiation. The light on the example below produces ~250 µmol/m2 at a depth of ~60cm right below the lamp. You would get values above 500 µmol/m2 at least in the upper water layers.

But this is all a theoretical exercise. A tank will have plenty of places with minimum radiation even if 500 µmol/m2 reach the substrate level. These limits only have consequences if you place the bacteria in a box of glass in laboratory conditions where they are completely irradiated.

1642435194546.png
 
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Hi all,
I'll start a <"new thread as well">, but I'll put this here as well, because it is very relevant to this thread, and to the microbes that actually perform nitrification in our tanks.

Al-Ajeel, S., Spasov, E., Sauder, L.A., McKnight, M.M. and Neufeld, J.D., 2022. "Ammonia-oxidizing archaea and complete ammonia-oxidizing bacteria in water treatment systems". Water Research X, p.100131.

<"Ammonia-oxidizing archaea and complete ammonia-oxidizing Nitrospira in water treatment systems">.

cheers Darrel
 
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