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Water changes bad for beneficial bacteria

jameson_uk

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10 Jun 2016
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Headline for attention but someone posted on another forum that a friend was suggesting their twice weekly 50% water change schedule would be bad as it would starve the beneficial bacteria of ammonia and they would end up needing to leave the tank to stabilise.

Got me thinking of two things...
First off is how long ammonia exists on the aquarium. Given that people dose 2ppm+ when cycling and expect it to be gone in 24 hours and whenever you measure it we expect it to be zero suggests that it is consumed pretty quickly.

The second is how long BB can survive without ammonia. I know there are a couple of threads which say that it needs oxygen to survive but I couldn't find anything that suggested how long they would last without food.

I know plants play into this as I guess in a heavily planted tank the ammonia rarely makes it to nitrification and is consumed by the plants before then. How would this differ in a non planted tank?
 
Hi @jameson_uk

If I were to go through my collection of scientific papers on this topic, I could probably give you a detailed reply. But, this is one of those situations where I prefer to turn this around and ask the person who first proposed this idea to substantiate this suggestion. Otherwise, in my opinion, this is just hearsay.

JPC
 
Hi @jameson_uk

If I were to go through my collection of scientific papers on this topic, I could probably give you a detailed reply. But, this is one of those situations where I prefer to turn this around and ask the person who first proposed this idea to substantiate this suggestion. Otherwise, in my opinion, this is just hearsay.

JPC
Totally. This was more that is piqued my interest. Particularly when you think the standard view is that ammonia should never show up but it must constantly be being added to the tank.
 
The only thing that could be of an issue is if the tap water has Chlorine in it, this is a disinfectant added to tap water by the water company to sterilize it. So if it contains this it could also kill bacteria in the tank and even have an ill effect on the livestock. Thus you should make sure that this isn't in the water.

The beneficial bacteria responsible for the nitrogen cycle are mainly living and find their food in the substrate, in and around the plant roots and in the biofilm that develops on the glass and hardscape. They are not really happily free swimming around in the water column. There is nothing for them to find in the water... :) Thus you can water change as much as you like it will have no ill effect on the bacteria as long as it is healthy clean water.

Decaying organic material, leftover fish food and fish poop contains ammonia, how much, and how long it takes for the bacteria to convert it is hard if not impossible to determine... But since all this material sinks down into the substrate and starts its decomposing process there, than also all available ammonia will mainly be in the substrate. Very little will leach back into the water column. If you reach a point that ammonia is measurable in the water column it means the substrate is much too dirty or mechanically disturbed (by hand).

Thus as long as you do not have too much measurable ammonia in the water column than how long it takes for the bacteria to convert what's in the substrate is rather irrelevant. There is nothing for you to worry about.
 
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Headline for attention but someone posted on another forum that a friend was suggesting their twice weekly 50% water change schedule would be bad as it would starve the beneficial bacteria of ammonia and they would end up needing to leave the tank to stabilise.
Hi again,

I was responding specifically to the above. But, @zozo is obviously correct. Indeed, it extends beyond chlorine to chloramine, which is increasingly used by water companies. So, perhaps the original suggestion from the friend had been misunderstood.

JPC
 
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Regards bacteria survival without ammonia it probably depends on which scientific paper you read. I'm not sure how closely related Nitrosospira briensis is to aquarium bacteria but apparently that can survive for 10-14 days.
Hopefully someone with more understanding than I can clarify.

Cheers.
 
So, if you reduce the amount of ammonia (by water changes) the population of BB will reduce.
But with less ammonia you need fewer BB to deal with the ammonia. No problem.
If the ammonia creeps up again the BB will enjoy a population explosion. Some bacteria can double their numbers in 20 minues if there is sufficient food.
Once established, the population of BB will fluctuate with the food supply and there will always be enough under normal conditions.
 
Does it matter? Either you are removing it through water changes or bacteria via the nitrogen cycle. As long as it's not there, who cares. If there is ever enough inbetween changes to support bacteria it will develop, and if there isn't it's not needed anyway.
 
The only way water changes will disrupt your microbial assemblage is through chlorine or chloramine. Maybe in another few years pesticides.

Ive never had any problems since switching to rain water.
 
I would suggest that any Ammonia added as part of an EI regime is EXTRA to that produced by tank inhabitants.
The bacterial colony in a filter has a constant supply of food as the amount of waste produced by fish stays the same.
Any Ammonia added as part of an EI regime WOULD be consumed by BB but there will ALWAYS be a small surplus until the 50% water change is done.
 
When I started fishkeeping I read this in several places, in relation to a Walstad tank which is what I intended to start with. Not doing water changes (plus adding ammonia, craziest advice ever :eek::eek::eek:) killed my first fish. I think things like that can be done by some people, but certainly not by beginners, and I don't like that it demonises water changes which are the number 1 thing to do weekly + when things go wrong. It's literally a dangerous idea for those unlucky first fish.

I'm still obsessed with the idea that were should chuck the term of cycling for new people and change it to maturing, to emphasise that time and growth of plants + bacteria is most important, rather than the abstracted scientific process of cycling which confuses beginners and makes them think they can cheat and speed things up by fiddling and doing excessive am/no/na tests. Not to say we shouldn't mention how the process works, but deemphasize people's control over it and myths about it like the water changes. Been thinking about working on a little ukaps foolhardy beginners guide to tropical aquariums, I go on a few forums and am often giving advice (basically just the above + use more plants) to newbies who are confused and have been given terrible advice from online +lfs
 
I seem to say this a lot but sorry to the Op for going off topic.

Been thinking about working on a little ukaps foolhardy beginners guide to tropical aquariums.

On the surface I think this is a brilliant idea but we have to have a degree of acceptance that there are different ways in which to cycle/mature aquariums.

In terms of planted tanks the holy grail would be to start with a high plant mass and ideally some fast growing stem plants, then after maybe six weeks livestock would be slowly added.
At the opposite end of the spectrum would be a tank set up from day one, overly stocked with fish and a single anubias nana petite, which technically for the sake of this example is a planted tank.

We should also consider the elephant in the room that is TESTING! We all know these kits aren't accurate but lots of us do it in secrecy, fearing ridicule if the secret ever gets out. When starting a tank how do we know when its safe to add fish if we don't at some point test for ammonia?

So yes a guide would be useful, but I think it should be approached with "Harm reduction" in the back of our minds and not a preached sermon of A is right and B is wrong.

Cheers.
 
I seem to say this a lot but sorry to the Op for going off topic.



On the surface I think this is a brilliant idea but we have to have a degree of acceptance that there are different ways in which to cycle/mature aquariums.

In terms of planted tanks the holy grail would be to start with a high plant mass and ideally some fast growing stem plants, then after maybe six weeks livestock would be slowly added.
At the opposite end of the spectrum would be a tank set up from day one, overly stocked with fish and a single anubias nana petite, which technically for the sake of this example is a planted tank.

We should also consider the elephant in the room that is TESTING! We all know these kits aren't accurate but lots of us do it in secrecy, fearing ridicule if the secret ever gets out. When starting a tank how do we know when its safe to add fish if we don't at some point test for ammonia?

So yes a guide would be useful, but I think it should be approached with "Harm reduction" in the back of our minds and not a preached sermon of A is right and B is wrong.

Cheers.
Oh goodness I hope I haven't opened a can of worms I didn't mean to!! It doesn't have to be for UKAPs, I was just thinking of writing on my own as a side thing during corona and seeing if it could help people. Obviously UKAPs is full of people with experience who love their hobby, so it's not really the target audience, but we do get beginners who do need some help. A big emphasis would be on researching more (like during those 6 weeks working out what fish would actually be right for people's tanks), and looking at journals here and things.

My plan for a guide was because people (including me) kill their fish when they start completely accidentally, they've got dodgy info from their LFS which they trusted (my LFS is great but not all are), or they did loads of research online and found conflicting information so just picked one (often the wrong one). I never found a how-to guide that comprehensively explained things to a complete beginner, I did everything I thought was correct, but it wasn't. It wasn't until I came here that I started to understand things better, and see the aquarium as a whole system. So my thought was to write a guide for me when I started basically lol

It would explain basic concepts in a clear way, with examples for how people can do things, with links for extra reading on different topics, but always being clear what is essential an what is optional, and what is something for a complete beginner vs someone who has experience. Obviously there are many different ways of doing things, but I think picking one way (6 weeks maturation with heavy planting from the start & substantial regular water changes) is the best way for beginners to set them up to have a beautiful and enjoyable aquarium which they can build from. My angle is that if a guide can be created that people can follow and help reduce the number of fish killed through mistakes then that's a good thing. I know that people should just go and buy + read more books, but lbr people avoid doing that now with the internet.

When I mentioned testing, I mentioned it because I was fully obsessed with testing when I started, testing every day to see the levels change. If you go onto reddit (which I do sometimes), you will see LOADS of people doing things, convinced that their tank with 6 stems in it is cycled after 2 weeks, and when their fish die they are confused. Test kits are useful, but they aren't tools to make things go faster, they aren't better indicators when beginning that things are ready than time and plant growth is. New people can't read an aquarium as an experienced person can, so they rely on test kits, but they also don't tell the whole story.
 
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The bacteria are going to be the most bomb-proof things in the tank. There's nothing you can do (other than adding antibiotics) that will negatively affect the bacteria without first killing everything else. You don't have to worry about the health of the bacteria and that includes most definitely no need to try to feed them ammonia. ;)
 
Without fish waste there shouldn't be any ammonia.
If using substrate that leaches ammonia, follow the maker's recommendations for timing.
If adding ammonia to 'cycle', stop. :)
Ok fair point and to be clear I'm not advocating adding ammonia although I have done it in the past.

Regards substrate and purely to play devils advocate ~ I'm using ADA power sand and the makers recomendation is to examine water quality with something called a NH4 pack checker before adding live stock.
 
Hi all,
In terms of planted tanks the holy grail would be to start with a high plant mass and ideally some fast growing stem plants
Yes, <"lots of plants are a prerequisite">. <"Floating plants are best">, because they have access to aerial CO2. Emergent plants would be even better, but more problematic for most people.
but lots of us do it in secrecy, fearing ridicule if the secret ever gets out.
<"We honestly aren't anti-testing">, the issue is with the accuracy of the testing, not the principle. I would really <"like to know what the water parameters in my tank are">, but if some-one tells me they have "no nitrate", but their plants grow like mad, <"then I know what I trust">.
how do we know when its safe to add fish if we don't at some point test for ammonia?
Just let the plants grow in, <"plant/microbe nitrification"> is much more efficient than "microbe only". I appreciate that it requires a leap of faith, but it honestly is true.
Regards bacteria survival without ammonia it probably depends on which scientific paper you read.
It does, but since we had DNA libraries it has been demonstrated that <"the "traditional" bacteria">, that we thought were responsible for nitrification, and require high ammonia loadings and pH <"don't actually occur in aquarium filters">. Have a look at <"Bacteria in a bottle">, if you want <"a scientific paper"> to read <"Bagchi et al (2014)"> is a reasonably accessible read for non-scientists.

cheers Darrel
 
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