BBA came back!

[Matti]

I had a long time BBA issue which I finally solve by soaking all the Buses and Anubias in bleach. BBA gone and everything was fine for a while. Then I decided to boost the plant growth with an inline CO2 diffusor. I was kind of lazy and only watched the drop checker. When I finally measured KH/PH values the CO2 were way of the charts! And the BBA came back, all this in couple of days!
So lesson learned, too little CO2 is bad, and so is too much CO2. Now I'm trying to find the right balance: lights, ferts and CO2. And spot treating plants with H2O2, which really sucks!

 

[arcturus]

I had a long time BBA issue which I finally solve by soaking all the Buses and Anubias in bleach. BBA gone and everything was fine for a while. Then I decided to boost the plant growth with an inline CO2 diffusor. I was kind of lazy and only watched the drop checker. When I finally measured KH/PH values the CO2 were way of the charts! And the BBA came back, all this in couple of days!
So lesson learned, too little CO2 is bad, and so is too much CO2. Now I'm trying to find the right balance: lights, ferts and CO2. And spot treating plants with H2O2, which really sucks!

The amount of CO2 is not necessarily good or bad. If you have very high CO2 concentrations in the tank, then the plants would thank you - but the livestock would not live to tell you what they think about it

Anyway, what is bad is having a deficiency of nutrients and/or deficiency of CO2 for the amount of light you are providing. But even if CO2, ferts and light are in balance, you will run into issues if the CO2 is not properly distributed - this requires excellent flow across all the tank. In any case, the actual triggers for BBA are not understood.

 

[jaypeecee]

Then I decided to boost the plant growth with an inline CO2 diffusor. I was kind of lazy and only watched the drop checker. When I finally measured KH/PH values the CO2 were way of the charts! And the BBA came back, all this in couple of days!

Hi @Matti

It appears that BBA are a species that prefer to uptake inorganic carbon in the gaseous form, i.e. CO2.

Out of interest, did you record the dKH and pH values that you mention above?

JPC

 

[Matti]

Hi @Matti

It appears that BBA are a species that prefer to uptake inorganic carbon in the gaseous form, i.e. CO2.

Out of interest, did you record the dKH and pH values that you mention above?

JPC

I did, before my KH/PH used to be 6/7=30 CO2. After installing the inline diffusor KH6 and PH6, that's 180ppm CO2! We are talking about severe CO2 poisoning.
And for the first time I have BBA also on my lily pipe. So it's not only about how well the plants are growing, it must be with the high CO2 levels themselves.

 

[jaypeecee]

In any case, the actual triggers for BBA are not understood.

Hi @arcturus

It is my understanding that some of the potential triggers for BBA are understood. But, I need to substantiate this with evidence. I'll re-visit my ever-growing library of scientific papers that I've pulled together. I retired many years ago but I've never been busier!

JPC

 

[jaypeecee]

We are talking about severe CO2 poisoning.

Hi @Matti

I sincerely hope you didn't have any livestock in this tank.

JPC

 

[arcturus]

I did, before my KH/PH used to be 6/7=30 CO2. After installing the inline diffusor KH6 and PH6, that's 180ppm CO2! We are talking about severe CO2 poisoning.
And for the first time I have BBA also on my lily pipe. So it's not only about how well the plants are growing, it must be with the high CO2 levels themselves.

Where are you getting these CO2 values from? Are these from CO2/KH/pH tables? I truly doubt you have anything near 180ppm of dissolved CO2 in the water.

What is the pH level of the tank’s degassed water? And pH of tank water during injection? Colour of drop checker?

 

[Hufsa]

Those blooming CO2 tables should be illegal, they're so misleading
@Matti long story short, those CO2/ph/kh tables can only be used for water which the only acid source is CO2. Aquarium water has many other sources of organic acid, and the table will therefore give such wildly inaccurate numbers. Luckily you have not had 180ppm CO2 in your tank.

 

[erwin123]

I suspect that BBA on your Buces but not others has something to do with flow patterns. One experiment you could do after zapping the BBA is to move the Buces to a different location in your tank to see if BBA reoccurs?

 

[Matti]

Hi @Matti

I sincerely hope you didn't have any livestock in this tank.

J

Those blooming CO2 tables should be illegal, they're so misleading
@Matti long story short, those CO2/ph/kh tables can only be used for water which the only acid source is CO2. Aquarium water has many other sources of organic acid, and the table will therefore give such wildly inaccurate numbers. Luckily you have not had 180ppm CO2 in your tank.

Something was still wrong as the PH had been very stable around 7-7.2, and suddenly fell to 5.9-6.0. Only thing that had changed was the new inline diffusor. And the same time the BBA came back. All this in couple of days.

 

[Matti]

I suspect that BBA on your Buces but not others has something to do with flow patterns. One experiment you could do after zapping the BBA is to move the Buces to a different location in your tank to see if BBA reoccurs

It's not only on the Buces, also on Anubias and even on Hygrophila. And inside my outflow lily pipe! I think the smoking gun must be the excess levels of CO2 that had been in the tank for couple of days.

 

[Matti]

Those blooming CO2 tables should be illegal, they're so misleading
@Matti long story short, those CO2/ph/kh tables can only be used for water which the only acid source is CO2. Aquarium water has many other sources of organic acid, and the table will therefore give such wildly inaccurate numbers. Luckily you have not had 180ppm CO2 in your tank.

A pH drop from 7 to 6 in couple of days indicates a tenfold increase in the acid concentration. And the only source of acid I can think of is the CO2. I use the PH/KH tables to measure CO2, as I don't know any other way to do it. The drop checker is just a PH-test, doesn't give you any CO2 readings.

 

[Hufsa]

I use the PH/KH tables to measure CO2, as I don't know any other way to do it. The drop checker is just a PH-test, doesn't give you any CO2 readings.

You cant measure CO2 in an aquarium that way, that is the problem.

Measuring dissolved gases is difficult, but the only tools we have available that do not give incorrect numbers like the PH/KH table is the dropchecker, a ph drop from fully degassed aquarium water, and a ph profile.
The dropchecker is not a PH test, as long as you have filled it with 4dKH water it is measuring the amount of CO2 in the little air gap above the solution.

There are several recent threads about why and how to perform a complete PH profile, I think you should read them and it will be more understandable then.

 

[arcturus]

A pH drop from 7 to 6 in couple of days indicates a tenfold increase in the acid concentration

Correct. A 1.0 pH drop is a tenfold increase in acidity since pH is a logarithmic (log10) scale. But all the rest of your reasoning is unfortunately wrong.

And the only source of acid I can think of is the CO2.

No. The acidity will increase as CO2 is injected due to the formation of carbonic acid. But there are multiple chemical processes in tank that are constantly changing the pH. Just to name a few: mineral content of rocks, wood, soil, plant photosynthesis and respiration, livestock respiration, fertilizers, food, bacterial activity, nitrification processes, ... This means that we cannot rely on the pH of the tank water to determine CO2 concentration since we cannot factor in the effect of all these processes.

I use the PH/KH tables to measure CO2, as I don't know any other way to do it.

The pH/KH tables are only applicable to controlled water conditions since they are calculated according to chemical formulas that make assumptions about the water parameters. These assumptions are not applicable to an aquarium or any other natural environment. You cannot even properly measure the KH of your tank without specialized equipment (the KH test kits are measuring much more than KH). What the pH/KH/CO2 tables is telling you is absolutely meaningless.

The drop checker is just a PH-test, doesn't give you any CO2 readings.

Yes, it is only a pH test. But it gives you an accurate reading of the CO2 concertation in the water.

The drop checker is not measuring the pH of the tank water but the pH of a calibrated solution (usually KH = 4° dH) inside the drop checker. The acidity of this solution will change according to the amount of CO2 in the water that will degass into the air gap inside drop checker. This means that the colour of the drop checker only changes as a result of changes to the CO2 concentration dissolved in the water. In contrast, the pH of the tank water will change not only because of injected CO2 but also because of dozens of other process that we are not controlling.

The issue with the drop check is that it is a colour-based test that is hard to read precisely, its reading depends on the location in the tank, and takes a very long time to react to changes in CO2. Even with these limitations, the drop checker provides a precise measurement of CO2 concentration. The drop checker is actually the only CO2 measurement you can use...

Read a <summary of the problem here>, and a <more authoritative sticky thread here>. There are dozens of other threads discussing this same topic at UKAPS since it is a recurring topic, often fueled by these silly pH/KH tables...