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What exactly causes BBA? Part 2 - Bacterial imbalance

Hi all.

So basically the algae was living it up in my tank. I couldn't bare looking at it so I removed it all (again). I've also put my t8 fixture back on without reflectors and gone back to 'low light' plants. I bought some driftwood and tied some Anubis to it but the wood is just floating at the moment. It will sink in time. The plants I salvaged seem to be managing the lower light well and I am dosing liquid carbon. No additional ferts yet as I'm just going to see how the plants fare. All seems good at the moment. The wood is blocking some light and flow but when it sinks we should be ok. Will probably continue to do water changes weekly but maybe 20%. Oh I also added purigen to the filter.

So to get the topic back on track I have been wondering. Articles suggest that nitrifying Bacteria thrive in ph ranges from mid to high 7s. They also suggest that nitrosomonas growth is inhibited at ph 6.5 and all nitrification is inhibited at 6.0. If this is the case one might assume that bacterial colonise are small in a co2 injected tank where ph ranges are low <6.5 since the growth of bacteria is inhibited. If that includes inhibitation of heterotrophic bacteria also then ammonia production via fish will be taken up primarily by heavy photosynthesis and that breakdown of organic matter occurs more slowly. Even if this does not include inhibitation of heterotrophs then ammonia production by heterotrophic breakdown of organic matter should still be being controlled by heavy plant mass and photosynthetic rates providing light is not excessively high and the plants ammonia uptake rates match the rate of production. If we still believe the high light + high ammonia production is a factor in algae trigger then we can see how plant trimming/culling poor growth could allow temporary accumulation of ammonia that would trigger an algae bloom. Perhaps algae sense low co2/ph and use excess ammonia plus light as a trigger.

In my case I switched co2 injection off since I believed that the co2 was less than 6. Co2 on 3 hours before lights in a <3dkh tank is not a good idea. Then when I suddenly ceased injection due to fish distress my ph went back to its fairly stable level of 7.8 (ph pen) this would have enable rapid production of heterotrophic bacteria (white cloudy water) and subsequent rapid production of ammonia through breakdown of organic matter (soil substrate) then because nitrifiers are depleted and take time to grow and plant mass has been significantly reduced (which it was) excess ammonia was produced which led to a rapid (and I mean rapid) production of at least four types of algae that covered all plants, gravel and glass. Any thoughts?
 
Soilwork,

I think this is a really clever hypothesis:

- High CO2 lowers pH and (in tanks where pH is not initially very high) leads to inhibition of all types of bacteria growth as pH below minimum. Increasing CO2 means a bigger pH drop, which may mean it is a more effective control.

- High CO2, high light, high (healthy) plant mass leads to high absorption of ammonia/ammonium, preventing algae from benefitting.

- Reduce CO2 injection and the pH won't go as low, meaning that the heterotrophic bacteria can grow, at a faster rate than the autotrophic bacteria (particularly if heterotrophic bacteria were less sensitive to low pH levels).

- Reduce plant mass (trimming) and you reduce the amount of ammonia being absorbed by the plants, meaning less competition and enabling algae to benefit.

- Increasing O2 overnight, drives off CO2 (increasing pH) and provides O2 for bacteria to grow. Providing organics not too high, heterotrophic may help clear up overnight. Ammonia released provides food source for autotrophic bacteria to multiply. With sufficient CO2 at lights on, plants absorb ammonia, helping to prevent algae from growing excessively.

Andy
 
There is logic in what you are saying.

The main reason, I think, why nitrification is inhibited at low ph(6.5 and below) is because there's very little ammonia at that ph. Nitrifying bacteria uses ammonia and not ammonium for nitrification. When there's none or little, their population dwindles to match availability. Plants on the contrary are benefited because they prefer ammonium as a nitrogen source even though they can take up ammonia too. On another hand high ammonium and low plant mass/damaged plants may trigger algae outbreaks as you suggest....Most people that have planted and co2 injected tanks are "allergic" to off the shelf tests so they've got no idea whether they have measurable ammonium on and off that possibly triggered the algae outbreak in the first place....
Why would one test if their fish are just fine...ammonium is almost non-toxic to fish as long as it stays in that state. However, I can't believe that a person that pokes the substrate every so often to re-arrange their aquascape doesn't have some mini ammonia spike(0.25ppm and the likes) which is enough to trigger diatoms at least which is a sure sign of a sudden rise in ammonia/ammonium.

If you switched the CO2 off, the ph went up meaning that depending on temperature and other factors, that ammonium converted back to ammonia. If at that moment nitrifying bacteria and oxygen are not enough to consume the available ammonia, other organisms will take advantage, be it fast reproducing facultative heterotrophic bacteria(white bacteria bloom) or algae species of some sort. Even plants need time to switch from one type of nitrogen source to another and use energy to do so. When the nitrifying bacteria and/or plants catch up, the organisms that initially multiplied to handle that same issue will dwindle as nitrifying bacteria and plants are more competitive, providing there's enough oxygen, co2 and nutrients for them to do so.
 
Thanks to you both. Andy, you said what I wanted to say much more tidily haha and SC, that is a great point about ammonia/ammonium ratio at lower ph I forgot about that fact. So I'm kind of thinking that high pressurised co2 users are relying heavily on plants, to back up the system and when something goes wrong the nitrifiers are not there in large enough numbers to help reduce ammonia levels which would otherwise be detrimental to the ecosystem...enter mr algae...it is not a predator but a saviour, a protector of the ecosystem. It will remove harmful ammonia because of its rapid reproduction rate and provide oxygen to support life. Good old mr algae. There at the beginning, be there at the end.
 
SC I re-read your post and that is definitely the gist of what I meant. Particularly the second paragraph however, it is still just a hypothesis.

The funny thing is, there is a member on another forum I frequent where this exact same thing seems to have happened. Basically he/she had a low light tank with pressurised co2 that was balanced well with a thriving carpet. Water changes are minimal and no need for much ferts.

Their co2 ran out and it took them a week to notice. Major algae outbreak. The co2 is back up and running now but they have a ph around the mid 6's. And a Kh of 2.5.

Here is the link.

http://www.aquariumadvice.com/forums/f24/algae-problems-55g-346816.html
 
Perhaps because of that high pressurised co2 user's tanks are quite more sensitive to algae outbreaks for that same reason you suggested soilwork, because the accidental drop in co2 brings the ph back up which in turn triggers a chain of events including algae.... Maybe these issues are not due to reduction in co2 but the ph going back up every so often.

There was a very knowledgeable forum member here that proposed the idea(supported by a ton of scientific papers) that the most co2 concentration plants need is at level between 6ppm-14ppm depending on species(something in that range). He claimed that 20ppm is the level of co2 which plants would consume at unlimited light!! and nutrients of course! But no-one uses unlimited light in an aquarium, unless you put the tank in the garden..
 
sciencefiction said:
Perhaps because of that high pressurised co2 user's tanks are quite more sensitive to algae outbreaks for that same reason you suggested soilwork, because the accidental drop in co2 brings the ph back up which in turn triggers a chain of events including algae.... Maybe these issues are not due to reduction in co2 but the ph going back up every so often.

There was a very knowledgeable forum member here that proposed the idea(supported by a ton of scientific papers) that the most co2 concentration plants need is at level between 6ppm-14ppm depending on species(something in that range). He claimed that 20ppm is the level of co2 which plants would consume at unlimited light!! and nutrients of course! But no-one uses unlimited light in an aquarium, unless you put the tank in the garden..
Click to expand...

Ph going back up. Nail on the head. In that link I posted. It does show you again how quickly Everyone pounces on nutrients.
 
sciencefiction said:
the most co2 concentration plants need is at level between 6ppm-14ppm depending on species(something in that range). He claimed that 20ppm is the level of co2 which plants would consume at unlimited light!! and nutrients of course!
Click to expand...

Perhaps the importance of the 30ppm concentration is the 1 pH drop it induces? Using a pH drop to prevent the multiplication of the heterotrophic bacteria, reduces the release of ammonia while the lights are on, meaning less nitrogen compounds for the algae to create proteins and grow.
 
AndyMcD said:
Perhaps the importance of the 30ppm concentration is the 1 pH drop it induces? Using a pH drop to prevent the multiplication of the heterotrophic bacteria, reduces the release of ammonia while the lights are on, meaning less nitrogen compounds for the algae to create proteins and grow.
Click to expand...

Yes, I agree Andy. CO injected tanks are different. But sometimes what one thinks is helping is actually masking the main issue and making it worse.
There's no issues with heterotrophic bacteria in any tank as long as the tank is balanced and it isn't the only functioning bacteria. Heterotrophic bacteria releases ammonia, co2 and other gasses due to the present organics in the tank. They are the ones that produce inorganic nutrients from organic substances, for the plants to handle. In a high tech tank one doesn't care for that because one doses "unlimited nutrients" via EI and injects co2 hence heterotrophic bacterial decomposition is not a needed process. That's how it works for people. Wipe clean the tank, large water changes and rapid plant growth. You mess with any of these and you get yourself algae because there's no back up bar your own hands and free time.

That's why I think Co2 injected tanks are a very unstable system. When you drop the co2, the issues that arise may not be due to a "co2 deficiency" as most here express themselves but due to the slower ammonia/ammonium consumption by plants. In addition, with consistent low ph levels one disrupts the healthy balance of nitrifying and heterotrophic bacteria or at least the type of bacteria that are most capable of being a back up for inefficient "plant bio-filter.

If you don't play around with your tank trimming too much at once or if not relying on very high level of co2 to produce a certain level of plant growth which in turns consumes a certain level of ammonia that your fish and tank produce, then you are fine. Meaning that a low tech tank with consistent low ph that never varies, and high plants mass is a lot more stable than the same tank with injected co2 because everything in it is stable, from plant growth to ph, etc.. Plus certain species of plants have different consumption levels. Changing the species in a tank(new aquascape) changes the consumption rate altogether...Low tech tank keepers tend to just let the same plants grow and regrow for years..

I keep my tanks in hard water with rock solid ph of 7.4. I can leave my plants die of nutrient starvation to the point they start falling apart(I've got issues with iron availability in my hard water and nitrogen due to the large water changes I do and I forget to dose nutrients) and I still get no algae of any sort when that happens. The reason is because I have heavy filtration, ton of surface agitation to support it via oxygen, etc.. and suitable conditions for nitrifying bacteria. The only times I get algae is via overfeeding/overstocking/lack of water changes, when my plants and filtration are insufficient in handling the bioload.

At the same time I've destroyed perfectly healthy and non-deficient plants by overfeeding my fish consistently, resulting in diatom, blue green algae and black beard algae outbreak in the same order, suffocating them to the point of complete destruction...It is a certain thing when I raise fry and feed too much....Plant health and algae appearance in my opinion are unrelated unless there are other factors out of whack in the tank. Algae destroys plants but algae is not triggered by poor plant health in otherwise well established system in which the bacterial population is intact and not shocked on regular basis. One can also argue that high co2 in itself have a bearing on beneficial organisms in a tank, considering the small scale of eco system that is.

So in my opinion, high pressurised co2 systems are the most artificial and unsustainable method of keeping fish tanks. If one doesn't need very high co2 levels to keep plants at optimum condition, then it's worth exploring different methods. Diana Walstad mentioned in her book that low tech soil tanks produce an average of around 6-7ppm co2. I've seen the fast and healthy plant growth that such tank produces. I can't understand why one wants more than that. I grew a carpet of glosso in my soil tank at one point and every plant that I put grew well in it. Why would I want 30ppm of co2 and a tank I need to clean every other day..
I read that some fancy plants need high levels of co2 to be healthy. At the same time I read that the co2 compensation point can be increased by more light. A lot of low tech tanks can't grow plants despite the soil substrate because people are told to go very low on light, and so they do resulting in just anubias and crypts surviving. In my 5 foot tank while all my lights were working, I experimented by moving plants that didn't do so well at first by moving them from the shadier spot to high light spot. They immediately improved. I remember hydrophila pinnatifida was specifically benefited by that. My glosso carpet died two weeks after two of my led strips failed, i.e directly related to lower light. In fact majority of my plants melted after that. I've kept the tank in low light since and now I've got just anubias and crypts, from well over 20 species of plants 🙂

Sorry for the rant...🙂
 
I've posted these before but here is some glosso and bacopa carpet pictures from a low tech. I ripped the bacopa out because it grew like weed and decided it wants to grow horizontally. It wasn't supposed to do that, it creeped from the middle part of the tank to the front where it got itself more light, lol.
73e9fa3c-07c1-4388-b5fb-9a36c63bda56_zpswbuaeibb.jpg


And the glosso. It grew slower than the bacopa but steady and completely horizontally.
Tank13_zps6298fca5.jpg

463c333f01d22533ec8550508eeade84_zpsi3a1rtdg.jpg

So go argue tanks need 30ppm of co2 to grow most plants well and reduction of co2 to below that level means the demise of plants and algae...
 
+1 although my thoughts are a little more open in the fact that if people want to use high light and high co2 that is their prerogative and each to their own. Also people who do this also want to grow and support a variety of species with different needs and uptake rates en masse and very quickly at that. Therefore I would explain to those people the risks of using high light/high co2 then leave them be to make up their own mind.

Perhaps this is why people correlate algae with fluctuating co2 when rather it is long term fluctuation of ph that is often heavily influenced by carbonic acid. In my case this is really the only thing I could think of.
 
Another thought on the topic. If our hypothesis holds value then we could assume that once algae as a whole has been given the green light to grow the type of algae is then defined by the components of the system. For example. Algal trigger + low phosphate = GSA, algal trigger + low nitrate/high organics = BGA, algae trigger + low organics = GWA, algal trigger + low dissolved oxygen + organic matter = BBA or in my case I had the components available to support several types of algae.
 
Scapefu did a podcast recently concerning adding vinegar to his aquarium and it having a positive impact on how healthy his tank appeared. The podcast spoke about various reasons why he believed this was. I think it being a carbon source was one hypothesis.

I was just throwing it out there that adding vinegar would also have the effect of reducing pH, in the same way that adding CO2 would.


Sent from my iPhone using Tapatalk
 
Or perhaps the reduction in ph shifts the carbon/bi-carbonate ratio more towards carbon which is a more efficient means of carbon uptake for the plants?
 
After talking about soil substrates here I finally re-did one of my "tanks". It's not a tank, it's a plastic 80l container I've been using as a fish tank since last year to house some cories due to a tank breaking. It had no substrate as I literally dumped the plants, fish and an old filter in it. Almost all my anubias landed in there, lots of it. I of course didn't dose anything afterwards and the anubias is sorry looking, deficient and discoloured leaves....But not a sign of any algae.
Last weekend I put a soil substrate covered with plain sand and I planted the majority of the anubias in the substrate. The soil is mineralized as I did it more than 1.5 years ago but never got to use it. I can't believe how excited I am to stare at a plastic bucket...🙂 The corys are happier too with the substrate. The problem is they twice unearthed some soil making a cloud in the tank....little devils...They love digging and it's the first time I use very fine sand over soil....May not work...
It will be also tough to balance a tank that is planted 80% with anubias. There are a couple of crypts, a couple of echinodorus plants and a stalk of hydrophila and there's no room left for planting anymore, lol. I currently don't own any floaters.....I am going to have to see how that combo of plants fairs. I hope quantity will compensate for the slow growth. Light is low but on 12hrs a day 🙂 I've been doing this with the same light over my other small tank without algae issues and very healthy plants.. so we'll see. So far the echnodorus grew a couple of leaves and a few new leaves of the anubias look healthy. I am going to have to regrow all these anubias again..
 
Aww man where's the pic? Lol. When you say low light. How low exactly? What is the ph of your tanks again? Btw does anyone know why I can't upload pictures straight from my mobile? Also please excuse me for not liking any posts. I really don't know what I'm doing here yet, still finding my feet.
 
Just reintroduced carbon injection to my tank and will ween off the easy carbo. The bubble rate is very low and the mist is slow. I've got good surface ripple from both filters to but I'm thinking if I can create low consistent co2 without dropping ph too much it should still work with my low lighting. Also the co2 comes on with the lights so no chance to drop ph. The plants should have some natural carbon to draw on until the co2 gets going. I will be monitoring ph closely.
 
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