BBA Help

[nijat11]

1. 800 liters 180smx80smx55sm
2. 6 months
3. Sump; 1 chamber multiple multiple sponges, 2-3 chambers seachem matrix and biohome (total 35kg). seachem purigen.
4. WRGB. 14:00-22:00 (W:80%, B:80%, R:80%, G:50%) 22:00-23:00 (WBR:15%)
5. ADA Amazonia V2 and fine gravel
6. Installed 2 weeks ago. Controlled by PH controller + separate valve for night. During the day pH drops from 7.1 to 6.4. Drop checker get lime green.
7. Tropica Specialized every day 20ml and Tropica Premium every day 20 ml
8. Every 7-10 days 50%
9. Multiple cryptocorynes, multiple echnidoruses, multiple buchephalandras, Rotala Roundofolia, Rotala Orange Juice, Rotala Wallichni, Alternathera reckini mini, Alternather Cardinals, Golden Nesaea, Ludwiga Super Red, limnophila hippuridoides, multiple anubiases, Java ferns, Java moss.
10. Lime Green During the day.
11. Angelfish - 12; Rummy Nose Tetra - 30; Kardinal Tetra - 12; Black Neon Tetra - 10; Corrydoras Sterbai - 10; Corrydoras Panda -10; Apistograma Ramizeri -4; Apistograma Columbian -2; Apistogramma cacatuoides-2; Ancistrus -4; L333 - 2; L340-1; Nerite Snails - 10.
12. Please see the attached full tank image and plants with bba

So here is the story.
2 weeks ago I have introduced CO2 to my aquarium (using pH controller + additional valve and aquamedic reactor) and also I have stopped dosing Easy Life Carbo. Recently I have noticed that BBA started to grow on edges of most of my plants.
So I would like to ask.
1) Should I reduce the light?
2) Should I reduce fertilizers?
3) Should I start to dose Easy Life Carbo again?
4) Should I cut all infected plants?
5) Any other advises from you experience is much appreciated.

 

[_Maq_]

I doubt anyone knows a guaranteed way how to avoid BBA. Observations indicate that slow-growing plants suffer most. And when saying 'slow-growing', I mean both slow-growing species, but also growth hindered by external factors. This indicates two things: (1) BBA like organic compounds (leaching from plants, but not exclusively), and (2) general improvement in plants' health makes situation better. CO2 injectors often mention issues with unstable supply of CO2; on that, I can't comment, for obvious reasons.

 

[hypnogogia]

4) Should I cut all infected plants?

Yes, that would be a good start. Also remove any damaged leaves as they will leach organics and attract BBA.

 

[Andy Pierce]

I would give amano shrimp a try. I think I have observed these and also otocinclus catfish having a nibble at BBA. In any event, I have a small amount of BBA in my tank and it has been stable over a long time so I suppose the collective clean-up crew which also includes nerite snails which you already have is keeping things in balance. 10 nerite snails in an 800 litre tank is not very many snails - you could easily boost this to 50 in the first instance since there's so much territory to cover.

 

[_Maq_]

Yes, but if one nerite snail dies it's a load of organics big enough to get a tank out of balance.

 

[nijat11]

Okay now another question. Should I switch from pH controller just entire day CO2 supply.
So now it open the valve until pH drops to from 7 to 6.35. Should I change anything here?

 

[xZaiox]

I wouldn't bother using a pH controller, especially if you have a buffering substrate (like your ADA Amazonia). The issue is, there are other factors that can influence pH such as substrates and tannins, and the pH controller can't tell the difference between these factors and CO2. This means that in a poorly buffered tank, natural pH changes can result in unstable CO2 through the controller. You're best off manually setting the CO2 by using a good quality needle valve, and doing pH profiles to ensure that the levels remain stable throughout the day. Then forget about it.

Typically a pH drop of 1.0 is required for a lime green drop checker; it indicates a 10x fold increase in CO2 concentrations, which from my memory (which is poor) this should indicate a 20-30ppm range. It's important that this 1.0 pH drop is from fully degassed tank water, NOT water simply taken from the tank before the CO2 comes on (because this may still contain some CO2). Take a small sample of tank water in a cup and leave it by the window for 24 hours, then take the pH of that - that's your baseline, and you should generally aim for a 1.0 drop from that reading.

Regarding BBA, there are so many theories but unfortunately we don't have the answer yet. It's likely multifaceted. Tom Barr seems convinced it's related to either inadequate or unstable CO2. I'm less convinced. I've had long standing issues with it in my tank despite stable CO2 (within 0.1 pH from start of day to end), and even trying high levels (yellow drop checkers with 1.4 pH drop). These CO2 changes didn't make a dent in the BBA. I have however, found a few things that help:

(1) Keeping the tank clean with good quality maintenance seems to help (supporting the idea of organics playing a role).
(2) Reducing excessive flow - this algae seems to love high flow areas, and I found that my wavemaker was making it bloom in areas where it reached. Turning off the wavemaker killed the BBA in those areas.
(3) Reducing iron (Fe) dosing. I was a little unsure about this one, and I'm still experimenting with it, but I think excessive Fe may be a potential trigger and/or encourage it's growth. Since reducing my dosage from between 0.5-1ppm weekly to 0.3ppm weekly, it's definitely not growing anywhere near as much anymore. I plan to reduce this further and see what happens.

Again though, it's likely multifaceted. I imagine that the triggers will be different in different tanks. Algae is opportunistic, and the conditions of their blooming is likely not a simple single thing.

 

[Andy Pierce]

It's important that this 1.0 pH drop is from fully degassed tank water, NOT water simply taken from the tank before the CO2 comes on (because this may still contain some CO2). Take a small sample of tank water in a cup and leave it by the window for 24 hours, then take the pH of that - that's your baseline, and you should generally aim for a 1.0 drop from that reading.

I've heard this before... how is that supposed to work? i wouldn't expect CO2 gas (vs dissolved CO2) to affect a pH meter, and if you leave a cup of CO2-injected water out exposed to air it's going to head off towards the equilibrium value of 0.5 PPM CO2 (the pH will increase). At least with the calculator I'm using a pH drop of 1.8 gets you from 0.5 PPM to 30 PPM. If you have a pH drop of 1.0 that only gets you to 5 PPM CO2.

 

[hypnogogia]

At least with the calculator I'm using

What calculator are you using?

how is that supposed to work? i wouldn't expect CO2 gas (vs dissolved CO2) to affect a pH meter

Not sure I understand what you mean.

 

[xZaiox]

i wouldn't expect CO2 gas (vs dissolved CO2) to affect a pH meter

I'm also a little unsure what you mean by this?

if you leave a cup of CO2-injected water out exposed to air it's going to head off towards the equilibrium value of 0.5 PPM CO2 (the pH will increase).

My understanding is that CO2 at equilibrium is between 2-3ppm. Those are just the numbers I've seen thrown around on various forums such as UKAPS, I can't explain why though

 

[Andy Pierce]

Sorry, forgot to add the link to the calculator, that's in the post now. For the pH meter, it is measuring electrical conductivity. Gas bubbles will have negligible electrical conductivity so unless your water is so fizzy that the gas bubbles physically obstruct the pH probe surface, they aren't going to affect the measurements. CO2 equilbrium at 2-3 PPM is also commonly mentioned, but that's simply a common mistake. Much more discussion here: Estimating CO2 injection rates in ml per minute

 

[xZaiox]

CO2 equilbrium at 2-3 PPM is also commonly mentioned, but that's simply a common mistake. Much more discussion here: Estimating CO2 injection rates in ml per minute

From my (albeit limited) understanding, I think the 2-3ppm value came from actual measurements of still water. It's probably likely that not all of the CO2 has off-gassed after 24 hrs. I know this is a veeery old post, but Tom Barr also seems to think the numbers at equilibrium are higher.

@dw1305 Darrel you got any up-to-date opinions on this CO2 @ equilibrium stuff? I've seen you comment on this stuff before, but wanted to know what your current opinion is?

 

[hypnogogia]

For the pH meter, it is measuring electrical conductivity. Gas bubbles will have negligible electrical conductivity so unless your water is so fizzy that the gas bubbles physically obstruct the pH probe surface

But CO2 dissolves in the water making carbonic acid. I can certainly measure pH drop with my CO2 probe, how else do you think folks do their pH profile?

 

[_Maq_]

My understanding is that CO2 at equilibrium is between 2-3ppm.

Within temperatures about 20 to 25 °C the equilibrium is about 0.5 ppm CO2. In a 'live' water, i.e. inhabited by microbes a.o., 2 to 6 ppm are normal, while the higher concentration suggests quite a high biological oxygen demand (eutrophic water).

 

[LMuhlen]

Within temperatures about 20 to 25 °C the equilibrium is about 0.5 ppm CO2. In a 'live' water, i.e. inhabited by microbes a.o., 2 to 6 ppm are normal, while the higher concentration suggests quite a high biological oxygen demand (eutrophic water).

Out of curiosity, when we perform this ritual of storing a small sample of water for degassing purposes (or we actively shake, aerate and/or mentalize at the sample), we expect to reach the equilibrium of the CO2 concentration with the atmosphere. Do you think this sample will still have a considerably higher CO2 concentration due to it being "live" water, even when separated from the tank?

 

[_Maq_]

Do you think this sample will still have a considerably higher CO2 concentration due to it being "live" water, even when separated from the tank?

I've read that 1 cubic centimeter of sea water - much less 'live' than our tanks - contains millions of bacteria and even many more viruses.

But an easy way to degas water is to boil it. It'll lose all CO2 and most bacteria will lyse.

 

[Andy Pierce]

What I still don't understand is the logic behind "degassing" the sample before measuring the pH...

 

[Ria95]

(1) Keeping the tank clean with good quality maintenance seems to help (supporting the idea of organics playing a role).

Pretty much this, start at 1 and go down the list. I will add that you should be the biggest and baddest ’algae eater’ in your tank. You can do in seconds what it would take animals or microbes days.

I don’t know much about probes, but could it be some of the basics are off? As far as I understand a pH probe is at its roots a volt meter which displays mV as a pH value. Conductivity meters are something different and measure in Siemens (1/Ωm).

 

[xZaiox]

What I still don't understand is the logic behind "degassing" the sample before measuring the pH...

I've noticed that degassed water in a small cup left by the window will usually have a different pH than just measuring the tank water before lights on, at least, that's my own experience. Perhaps it's something to do with surface area? I can't really explain it, but I guess the small sample in a cup is more likely to reflect the 2-3ppm content.

I will add that you should be the biggest and baddest ’algae eater’ in your tank. You can do in seconds what it would take animals or microbes days.

Wise words

 

[hypnogogia]

What I still don't understand is the logic behind "degassing" the sample before measuring the pH...

Basically knowing what the pH is when CO2 is only at natural equilibrium level…therefore takes all other sources of acidity/alkalinity into account when measuring pH due to CO2 drop.