[ibebian]

A question to those who have BBA-free tanks: can you share some of the best performing plant species you have in there?

I just finished the Allelopathy chapter of Diane Walstad's Ecology of a Planted Aquarium, and it was fascinating. Admittedly, many of the references to various bio-organic compounds went over my head, but I'm pretty fascinated with the general concept. In it, she references a number of species that inhibit blue-green algae and green algae. For those that haven't yet come across this term (I literally just learned myself), allelopathy describes a plant's ability to secrete chemicals that can positively and negatively affect other organisms, most often other plants and sometimes inverts/fish. It's fascinating because the effect is very nuanced, making it difficult to measure, and yet can offer plausible reason for sudden and gradual changes in flora/fauna behavior and performance.

Now I haven't finished the book yet so perhaps this will come to bear, but does anyone have anecdotes or know of references to plants that seem to produce negative allelopathic effects on BBA? Seems like this would be a great plant to cultivate since BBA is so prevalent and stubborn!

If enough people answer the question at the top, my hope is to see several plant types trending that could indicate phenolic activity. I totally submit this is naiive since there are many more factors that come into play here, likely with even more weight than allelopathy could ever play, but a curious exercise nonetheless!

 

[brwaldbaum]

https://www.researchgate.net/profile/Sabine_Hilt/publication/222868977_Allelopathic_inhibition_of_epiphytes_by_submerged_macrophytes._Aquat_Bot/links/02e7e530f23b6b946f000000.pdf

The author of the 2006 paper at the above link summarized her results as follows: "My findings of a lower vulnerability of epiphytes against allelopathic substances of submerged macrophytes are supported by results of a literature survey."

My research students found results consistent with the above paper. They did an experiment in which they quantified the phenolic content of the leaves of several aquatic plants and compared it to the mass of epiphytes growing on the leaves. There was no correlation.

 

[JJ09]

I bought hornwort because I read that it emits something that is supposed to inhibit algae. I do still get some brown algae and BBA, but definitely don't have as much GSA now. I do see bubbles forming around the plants on the water surface. However I don't know if the reduced alage is from something the plant emits into the water, or just because hornwort uses up so much of the excess nutrient.

 

[randym]

I have never really had a problem with BBA in 25 years of keeping various types of planted tanks (high tech to no tech). Other types, but not BBA.

I have had BBA take over when there's too much light and not enough CO2 or nutrients, but when I fix it, the BBA just fades away. I don't try to remove it or kill it, it just goes away.

Cladophora, OTOH...ugh. I have to remove that when it gets out of hand.