Iron, Flow and BBA

[simon_the_plant_nerd]

Wasn’t sure if this should go in filtration, algae or fertilisers so I’ve put it here.

I’ve notice BBA appear on the leaves of some of my plants. I’ve removed those leaves and disposed of them. There’s never been BBA in the tank before but it’s appeared on some Hygrophila Lancea and on some Cyperus Helferi.

The changes I’ve made in my tank recently is dosing iron (0.5ppm per week as DTPA) and I increased the flow with a power head. I’ve removed the power head as after a few days I decided it was too strong and going to return it for something smaller.

I’ve read a few threads where Iron dosing and high flow are mentioned as potential triggers for BBA but never found anything conclusive. My lighting hasn’t changed for months and maintenance schedule remains the same.

Just wondered if those two changes are still considered as triggers for BBA or if I’m drawing the wrong conclusions?

 

[dw1305]

Hi all,

I’ve read a few threads where Iron dosing and high flow are mentioned as potential triggers for BBA but never found anything conclusive.

The simple answer is we don't know what causes BBA, despite two very long threads <"What exactly causes BBA?"> & <"What exactly causes BBA? Part 2 - Bacterial imbalance">.

Iron dosing
If we looked at iron (Fe) dosing the argument, it is a bit if a strange one, but leads from adding phosphate (PO4---) as a control mechanism for <"green spot algae">, which we think must work by <"making iron unavailable"> in the <"water column">.

When iron becomes plant available in the water column the quickest response is often from a sudden flush of green algae, as soon as iron stops being <"Liebig's limiting nutrient">.

Flow
We think that high flow only indirectly "causes BBA", by <"deterring snail grazing">. I always have snails so I'm not sure what would happen in my tanks without snails.

cheers Darrel

 

[MichaelJ]

I’ve read a few threads where Iron dosing and high flow are mentioned as potential triggers for BBA but never found anything conclusive

Are you injecting CO2 ?

inconsistent CO2 due to lack of distribution or large variations are known at least partially to be a CO2 trigger - as a matter of fact if you actually really wish to grow BBA for aesthetic reasons (!), one source of recommendations is to add a lot of iron, fluctuate your CO2 levels and keep your lights on high for long hours.

As Darrel said above we do not know for sure what causes BBA... but it's very unlikely to have a BBA problem (or algae problem in general) if your tank parameters are stable in terms of nutrients (Fertilizers, minerals, CO2 and O2) and otherwise well maintained with a low amount of organic waste (i.e. regular water changes). Exact levels - unless grossly insufficient or excessive - of nutrient seems to matter much less than just keeping the levels stable.

Cheers,
Michael

 

[dw1305]

Hi all,

As Darrel said above we do not know for sure what causes BBA...

That is a still from Rachel O'leary's famous video <"BBA carpet"> where she had a tank with fantastic BBA (and I mean <"that in a good way">) which suddenly all detached for reasons unknown.

cheers Darrel

 

[simon_the_plant_nerd]

While that tank does look amazing, it’s not the aesthetic I’m going for. 😄

Since set up I have generally had few algae problems. Diatoms, then an outbreak of green spot but otherwise nothing. The BBA was a very small amount but undoubtedly BBA.

The recommendation in that article is that iron never exceed 0.1mg per litre. I was taking my cues from EI dosing and was aiming for 0.5mg/l to avoid it being limiting. So it sounds like I should reduce my iron if that’s correct? I haven’t seen any deficiencies in my floating plants or submerged so the dosing wasn’t reactive, just preemptive.

 

[MichaelJ]

The recommendation in that article is that iron never exceed 0.1mg per litre. I was taking my cues from EI dosing and was aiming for 0.5mg/l to avoid it being limiting. So it sounds like I should reduce my iron if that’s correct?

It depends... 0.5 mg/L or 0.5 ppm is indeed a lot of Iron. Personally I dose ~0.05 ppm every two weeks in my two densely planted low-tech acidic soft water tanks. Circumstances in your tank (picture and tank details would be needed) may call for more iron... say if you water is high on pH - at or above 7 - and chelated with commonly used EDTA you will need more to compensate for faster precipitation and thus shorter bioavailability, but the calculation and how much extra to add to compensate is dicy at best. Even if your water is slightly acidic it shouldn't be a problem to dose around 0.1 ppm but more may be needed if your Phosphate levels are high as well.

Here is a chart showing availability of Fe with various chelates as a function of pH:

Cheers,
Michael

 

[John q]

Like Michael & Darrel mention the exact trigger for BBA is unknown, and unlikely to be narrowed down to one specific item.


I don't personally buy high iron levels as being the main cause of bba, if that were true then we wouldn't see it in tanks that literally run on fe vapours.
Look at maq's tank.

Fe 0.01675

Pics taken from.

Maq's low-tech troubles

Here you can see, on the upper shelf, a series of four tanks which I named "Portugals". Their names from left to right are Branco, Azul, Vermelho & Preto (meaning White, Blue, Red, Black). Each of them is 70 liters net, and faithful to my standard, sandy substrate (0.6-1.2 mm), lighting 10 to 25...

www.ukaps.org

 

[simon_the_plant_nerd]

It depends... 0.5 mg/L or 0.5 ppm is indeed a lot of Iron. Personally I dose ~0.05 ppm every two weeks in my two densely planted low-tech acidic soft water tanks. Circumstances in your tank (picture and tank details would be needed) may call for more iron... say if you water is high on pH - at or above 7 - and chelated with commonly used EDTA you will need more to compensate for faster precipitation and thus shorter bioavailability, but the calculation and how much extra to add to compensate is dicy at best. Even if your water is slightly acidic it shouldn't be a problem to dose around 0.1 ppm but more may be needed if your Phosphate levels are high as well.

Here is a chart showing availability of Fe with various chelates as a function of pH:
View attachment 216796

Cheers,
Michael

That’s very useful, thank you. From what you have said I can say with confidence I have been overdosing Iron. I have a feeling that the FE DTPA I bought may last me for about a decade!

My tank is CO2 injected (drop checked lime green) with a GH of 6dGH give or take. ph goes between 6.5 and 7.5 roughly. I’m medium planted at the moment I think. Removed a few things that weren’t working out but plan to replace soon enough.

EDIT: Having read @John q post, I don’t necessarily think iron has triggered the BBA but I’ve observed that I probably dose too much of it.

 

[bazz]

I occasionally find a plant of BBA waving in the wind at the junction of the highest point of flow in my tank (opposite the outlets) and conversely find one under some Buce leaves now and again low down near the substrate where there is a lot less flow and probably also traces of organic decomposition.
It doesn't bother me in slightest and actually amuses me that I think it's just eking out an existence in the hope that something will go wrong so it can pounce like the grim reaper.

 

[si walker]

From one Simon to another, for a minute I thought that I had actually written you post!
Just recently i have been seeing the same mostly BBA growing around the outside edges of longer leafed crypts.
I don't think its anyway a cause but prefers areas of higher flow.
Potentially it spiked when my Co2 bottle ran out etc etc.
I dose Iron as well as ferts and the tank is 80% packed with plants and running for nearly 2 years i guess.

Have snails and loads of shrimp but i dont think they are into it?

Spot treating a bit of Glute to see what happens.

Good luck and keep us posted!

Ive said it before but some of you lot are like Scientists! Hmm maybe you are?

 

[jaisol]

I'm runing coldwater, and usually see BBA build up from Jan - May also GSA feb - May, like most it is in high flow areas, & there is probably more organic decomposition going on in the colder tempretures. Over the years I've found you can fight it tooth and nail, spending a lot of time doing so, or just get rid of the worst and wait a few months, all the plants recover over the spring / summer.

 

[simon_the_plant_nerd]

so it can pounce like the grim reaper.

I live in eternal fear.

don't personally buy high iron levels as being the main cause of bba, if that were true then we wouldn't see it in tanks that literally run on fe vapours.

@X3NiTH made a similar point this afternoon. He showed me a few of the shop tanks with BBA growing happily that absolutely no iron was being added to.

Potentially it spiked when my Co2 bottle ran out etc etc.

I accidentally turned my co2 down a while ago. I saw an outbreak of GSA within a few days before I realised what had happened. I then turned it back up without thinking and gassed a few Amano shrimp. Felt terrible about it for days.

Stability is definitely key in a healthy set up.

Spot treating a bit of Glute to see what happens

I’ve not tried gluteraldehyde as it sounds like nasty stuff. That said I have used hydrogen peroxide (something I have on hand anyway) with mostly good results.

Over the years I've found you can fight it tooth and nail, spending a lot of time doing so, or just get rid of the worst and wait a few months, all the plants recover over the spring / summer

I am seeing more evidence each day that patience is key in this hobby. I’m guilty of not having much of that!