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What exactly causes BBA? Part 2 - Bacterial imbalance

months ago: I was tired to trim plants every week, so I reduced light and correspondingly Co2 a little to let plants grow less... Some plants begun to die, BBA appeared after 2-3 weeks or so.

Makes sense to me. Dying plants means an increase in organics for the heterotrophic bacteria to feed on. Less O2 as well as less light and CO2. Observed an increase in BBA.

It would be so interesting to know if suffering (but not dying) plants released organics too.
 
It would be so interesting to know if suffering (but not dying) plants released organics too.
This is probably true. When plants are moved to tanks with lower light, below the threshold for life, they begin to die. Reducing CO2 but not reducing light should prevent this. Plants are able to grow fine under much lower CO2 levels in nature.
 
Agitation only accelerates gaseous equilibrium.
If O2 is 10ppm, agitation will accelerate equilibrium down to 8ppm. O2 concentration drops faster.
If O2 is 6ppm, agitation will accelerate equilibrium to 8ppm. O2 concentration increases.


No, but I didn't reduce light which caused plants to die.

All this makes sense, thank you Guest. Is 8ppm the absolute/typical O2 concentration of equilibrium?
 
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However, overnight all organisms are consuming oxygen (plants, fish, algae, bacteria). Surface agitation means that you're keeping it at the lower level, better able to keep in equilibrium with atmosphere.
But plant leaves can hold onto O2 bubbles for a long time. They don't suddenly rise to the surface but stay under/on the leaves until they dissolve. In my tank, Bolbitis will have some gas bubbles under the leaves that didn't completely dissolve overnight.

All this makes sense, thank you Guest. Is 8ppm the absolute/typical O2 concentration of equilibrium?
Yes, approximately, but it's directly related to temperature as well. Higher temps = low gas concentrations. Lower temps = higher gas concentrations.
 
Thank you for confirming Guest. All this discussion on Co2 concentration, light and plants potentially suffering because of low light, makes me think that having stronger light is probably better than too low light for preventing BBA. Of course Co2 must be proportionally high. Thoughts?
 
Thank you for confirming Guest. All this discussion on Co2 concentration, light and plants potentially suffering because of low light, makes me think that having stronger light is probably better than too low light for preventing BBA. Of course Co2 must be proportionally high. Thoughts?

This is the opposite of what people report. People typically report that high light plus less CO2 means more BBA.

If plants released organics when light was high and CO2 reduced below the level the plants were used to, I'd understand why you'd get more BBA.

I couldn't find any evidence this was true.
 
Thank you for confirming Guest. All this discussion on Co2 concentration, light and plants potentially suffering because of low light, makes me think that having stronger light is probably better than too low light for preventing BBA. Of course Co2 must be proportionally high. Thoughts?
I get BBA growing in low light tanks so light isn't a limiting factor for BBA growth. Higher light levels increase the speed at which they grow.
 
Reducing CO2 but not reducing light should prevent this. Plants are able to grow fine under much lower CO2 levels in nature.

If you reduce any nutrient dramatically (e.g. CO2) from the levels the plant was expecting, would it suffer. If plants in nature have always grown under a low level of CO2 (probably slowly due to availability of carbon), they aren't seeing an extreme change. However, if you suddenly halve the CO2 supply, wouldn't the plant respond to such a significant environmental change?
 
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However, if you suddenly halve the CO2 supply, wouldn't the plant respond to such a significant environmental change?
This is my previous question. I don't know the answer. If the answer is yes, that would explain a lot of the algal growth on leaves in such conditions. If no, then that raises a whole lot more questions. I do like the idea of using half the CO2 - slower growth and less maintenance - at the same light intensity.

That would also explain the CO2 deficiency with the twisted, stunted growth, if it is indeed a CO2 deficiency.

Also, in non-supplied CO2 tanks, certain plants tend to grow better in appearance. I don't know why that's the case.
 
So for a couple of weeks, I used less CO2 (15-25ppm) than before (30-45ppm). BBA started growing at rates never seen

Isn't this the experiment that you have just performed and found that if you halve the CO2 supply (same light intensity?) you do get an increase in BBA?
 
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Isn't this the experiment that you have just performed and found that if you halve the CO2 supply (same light intensity?) you do get an increase in BBA?
Yes, but I don't know if that's true in all instances. Also, I actually increased the light intensity slightly by lowering the fixture during those weeks so it's not carefully controlled at all.

I remember reading a post by someone (I think on TPT) who said that they got perpetual BBA for a long time and nothing he did got rid of it. Until he increased light intensity. Then all of a sudden, BBA disappeared from just that one change. Two possible reasons for this outcome: 1)increased light intensity improved plant health, or 2)increased light intensity increased O2 concentrations.
 
Hi all,
CO2 and O2 concentrations are independent of each other. True, more organisms will be respiring, taking in O2 and producing CO2 overnight, but CO2 levels will be less than injecting during the day. I think surface agitation at night stops O2 levels dropping too low, rather than CO2 levels getting too high.
I think that is what is happening at a gas exchange level. If you have a lot of water turn over etc. all gas levels are going to be closer to equilibrium with atmospheric gas levels.

Having a large "gas exchange surface area" is definitely an advantage in terms of oxygenation. As an example you can counteract the effect of high levels of organic pollution in reed beds for sewage treatment etc. by <"forced aeration">.

cheers Darrel
 
I think it is time to revisit this whole limitation concept. Liebig's law of the minimum has to do with scarceness i.e. not enough of something. All aquariums are limited to some degree. The light in an aquarium almost needs to be limited. It is nearly impossible to manage an aquarium in sunlight for example.


What you need in aquarium is enough. You need a ‘balance’. I am not sure of the correct word but perhaps it is equilibrium. When you have a deficiency that means you don’t have enough of nutrient x in the tank to keep plant A growing happily in the context of the rest of the ecosystem in the tank. (I hope that makes sense) What ei does is attempt to provide just a bit more than enough. It works on a sort of average need basis and attempts to exceed it.


Notice that we never suggest that the hardness of a tank should not be limited. We know that there are plants that need soft water and there are plants that need harder water. Plants are not universal in their needs. They are all adapted to their environment. Their needs differ.


Co2 is no different. It needs to be limited. Anyone who has suffered an end of tank dump knows that non limited co2 is a catastrophe. At the other end of the spectrum it doesn’t ‘need’ to be injected in a tank. Many of us run perfectly fine planted aquariums without injecting co2. Again, plants are not universal in their needs some of them can grow quite happily without additional co2. What you need is enough co2 to provide for the needs of your particular plants in the context of the rest of the chemistry of the system you are running.


Ei is not non-limiting. (It is always good to end on a double negative!)

Or something like that……………
 
It is nearly impossible to manage an aquarium in sunlight for example.
Then how do aquatic plants survive growing submerged in lakes and rivers receiving sunlight for several hours each day without being infested with algae? This has always confounded me and I've not read any explanation for this phenomenon.
 
Then how do aquatic plants survive growing submerged in lakes and rivers receiving sunlight for several hours each day without being infested with algae? This has always confounded me and I've not read any explanation for this phenomenon.

You can grow plants under sunlight without algae. Try a glass bowl with some soil to provide nutrients and lots of plants on the window sill or outside somewhere. It won't get algae in most cases. Don't dose nutrients in the water column though. Or setup two pots, one being dosed, the other not dosed and you'll see that green dust will soon coat the sides of the dosed one, perhaps other algae. I am not saying the problem is nutrients. I am saying the problem is nutrients in the water column, as they are easily salvaged by algae which doesn't have roots in the substrate and can't otherwise survive for long unless the water column is polluted on consistent basis.
Same in natural systems I think like rivers and lakes. As long the waters are not polluted, they don't get algae outbreaks. I don't think light is a trigger. It can be an accelerator when other factors are not in check but on it's own it won't trigger anything. Light is a an energy source, not the enemy.
 
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This is the opposite of what people report. People typically report that high light plus less CO2 means more BBA.

If plants released organics when light was high and CO2 reduced below the level the plants were used to, I'd understand why you'd get more BBA.

I couldn't find any evidence this was true.

Andy, I am afraid you missed the last part of my posting there: "Of course Co2 must be proportionally high".

What Guest posted above really makes me think something more specific, here is what Guest posted:

I remember reading a post by someone (I think on TPT) who said that they got perpetual BBA for a long time and nothing he did got rid of it. Until he increased light intensity. Then all of a sudden, BBA disappeared from just that one change. Two possible reasons for this outcome: 1)increased light intensity improved plant health, or 2)increased light intensity increased O2 concentrations.

Well... what about having too much Co2 compared with the amount of light? Can "too much Co2" being the problem? Just throwing thoughts out there guys... Could that give us an explanation of such an effect? I mean, I pump a lot of Co2 in my tank (80ml per minute in a 75gl tank!), because I want to prevent BBA, but it is actually always around anyway! And my light is not that powerful (40-50 PAR at the substrate). I am wondering if increasing light could even things out??!!
 
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It is nearly impossible to manage an aquarium in sunlight for example.

Bruce, watch this again:



Also, I have seen ponds with crystal clear water, no algae, and any sort of plants inside (not only water lilies, but Ceratophillum, Elodea and other submersed plants) under full sun. Of course I have also seen a lot of ponds with bad algae inside... but as scienscefinction said, I don't think it's the sun to blame. It is, there as well, an imbalance of some sort (nutrients? bacterial?)
 
Yes I have seen that. I would guess it is in a courtyard and in shadow much of the time. I did say 'nearly'. I think almost no submerged plants live in open water. Still a pond is not an aquarium.

I live at almost 6 thousand feet and the sunlight is very strong here. I swim a lot and in most of the lakes I can't see my own hand in the water.
 
As mentioned by some other people, invasive algae are the result of a mix of nutrients availability plus the right conditions of light and CO2. In oceans, algae bloom happen when nutrients are available as non-limiting factors and the temperature and light increase from colder waters to warmer, which also helps the growth. The increment of light allows also the algae to proliferate faster, but the light is not really the cause of it, just an additional factor.
In freshwater, especially in closed pools like lakes are steady rivers, the algae bloom is related to the eutrophy, which is also spammed by a combination of excess of nutrients in non-limiting circumstances plus light and low levels of CO2.

Heavy planted plants are less likely to suffer algae because the consuming rate of nutrients is higher, so the water depletes faster than recovers them, which avoids the problem, so far CO2 levels are right so the plants can do the proper photosynthesis. Without the right levels of CO2, the plants lose efficiency so nutrients start to accumulate allowing the growth of algae.
Less hours of light works because algae are more dependent on light to survive than plants (in general). By cutting light to the tank, the algae cannot grow. However, it does not help at all if you do not solve the issue why they appear, which is the combination of light + nutrients.
Cleaning the tank and removing wastes helps because of the mentioned bacteria in this thread: If enough dissolved and particle organic matter exists in the tank, the natural cycling of matter done by bacteria will become it into nutrients that sum up to the fertilizers and soils, leading to the mentioned statement of non-limiting nutrients.
Reducing temperature also helps, because the dissolution of gases in water depends strongly on that, which helps to have better CO2 levels in the tank. It also affect to the speed of metabolism of plants and algae, and when the last ones are having some control in the tank, a reduction of a couple of degrees can help.

In summary, under my criteria, we can split between actual solution, palliative solutions and radical solutions:

Actual solutions:

1. Control of nutrient levels: Water changes and control of the dosage of fertilizers (as done in ADA system during the first two weeks, basically).
2. Balance the nutrient levels: Check what you are adding to the tank and frequency to see if your parameters are under control. Sometimes the problem comes from deficiencies in iron or trace elements respect to the concentration in the macronutrients, so the real point here is not the amount of nutrients but the proportions between them, and here there is no magic answers as strongly depends on the amounts and type of plants, as well as light spectrum and temperature or soil characteristics, so it can be achieved only via experience and behavior of each tank.
3. Improve CO2 levels: By adding more CO2 or adjusting kH, or both.If CO2 is not a limiting factor under light conditions, then plants can get maximum efficiency in productivity.
4. Clean-up of filter media and mechanical removal of wastes and damaged leaves, so heterotrophic and remineralizing bacteria cannot make the day for the algae.

Palliative solutions:

1. Reduce the photoperiod of your tank to avoid or reduce the algae population in the tank.
2. Mechanical removal of algae when possible.
3. Addition of species that eat the algae.
4. Adjustment of temperature to increment CO2 levels and reduce metabolism speed of the algae.

Radical solutions:

1. Blackout: Some people have succeed cutting off algae populations with a black-out for several days. This will harm also the plants, so it is not very helpful, as the algae will come back, and probably even worse than before, if you do not manage to solve the problem that caused them in first place. Spring blooms in ocean over polar areas can help to understand what happens when you turn off the light some days, the bacteria degrade the wastes increasing the nutrients, and you turn on later the light.
2. Glutaraldehyde dosage: Apart from the fact the product is really toxic and dangerous, it can be very harmful for your tank if you do not control properly the dosage.
3. H2O2 dosage: The same as above when goes to the tank's health. As mentioned also, H2O2 will help to attack punctual spots of algae. It is bad idea to provide this to the tank as "normal" solution to prevent algae.
4. Rest the tanks: Which only will work if you learnt something about what caused the problem in the tank, so you do not make the same mistakes.

In general, the only way to really avoid algae pass by the actual solutions; palliative solutions are OK when you already have it and as a first approach to the problem; radical solutions should be only applied when all the other methods did not work or the algae already damaged your plants at such a level that you can risk them.

Of course, this is just my opinion about this topic, and there will be many specific cases requiring something else, or specific algae coming for different reasons.
 
I don't think light is a trigger. It can be an accelerator when other factors are not in check but on it's own it won't trigger anything. Light is a an energy source, not the enemy.
So under sunlight, the plants are most likely carbon-limited, as well as nutrient-limited. Can this be replicated in our aquariums? Is it these limitations that prevent such growth in our tanks or is it something else?

You can grow plants under sunlight without algae.
I've done this with Lilaeopsis mauritiana and no dosing. No algae and the plant pearled in sunlight. Which makes me think: if the plants use up the CO2, there will be a equilibrium differential between the water and the atmosphere. This would cause CO2 to rapidly dissolve into the water due to low concentration. Hmmm....
 
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