Anachris and BGA

[daveedka]

I read today that anachris releases an agent that kills/ prevents BGA (cyanobacteria) I have one tank with no anachris, and that tank is the only one that ever has BGA show up. Has anyone else heard this? Is it true?
I had no intention of adding anachris to the big tank as it didn't fit in the general plan, but could easily do so if it would make for less issues.
Any thoughts/ responses would be appreciated.
Dave

 

[Blinky]

That's really interesting! It talks about allelopathy in the book 'Encyclopedia of Aquarium Plants' by Peter Hiscock. Here's a bit of what he says:
"Allelopathy describes the production of chemicals by an organism that adversely affect another organism and/or advantageously affect itself. In the case of plants, these chemicals (called allelochemicals) are often readily produced to inhibit the growth of other plants or algae, or to prevent animals from eating the plant. [...]in the enclosed environmnet of the aquarium, allelochemicals can quickly build up, with various effects on some plants species [...]The allelochemicals produced by some aquatic plants have a particularly adverse effect on floating plant species and algae. This is one of the main reasons why a well-planted aquarium may not show signs of algae blooms, despite hight nutrient levels and strong lighting"
So if the allelochemicals can affect animals as well as other plants, I can see a photosynthetic bacteria being effected - it falls right in between the two! Sounds like the theory could be right, especially with what you've seen happening in your tanks. I love to experiment - I'd be inclined to put some Anachris in the tank and see what happens...

 

[daveedka]

My plan in the morning is to move in as many stems as I can free up from my other tanks. I then plan to clean out what BGA I can (there really isn't a lot but it does grow very fast) and see how things look after a week. The anachris won't be permanent in this tank I don't think, but we'll see. Once I put it in It will be there until my other plants fill out and increase in mass though. Thanks for the info, The experiment will be posted.
Dave

 

[Blinky]

I look forward to reading the results!
I sure wish I'd loved learning this much when I was in high school...

 

[plantbrain]

Let's talk reality:

Allelopathy has not been shown to exist in any natural aquatic system.
Anachrais(Egeria Densa is a plant I know very very well, it's a nasty weed here and I do control for the state.

It does not do anything as near as anyone can tell in practical planted tanks.

Now if you grind some Egeria up and put it on BGA(which species of BGA BTW? That is a very key piece of info. We don't know since they did not give a reference or did he? Or Diana Walstad?) That is not very realitistic in terms of what actually happens with live material.

Lots of things can be ground up and oput on things to inhibit growth, but if you ut them together ina tank, no interaction will occur.

There is one genus and likely just one species that causes the problem.
So unless the study was on that genus, it really doesn't tell you anything worth while about BGA.

Issue no #2.
What are the odds that all 300 species of plants have ther same effect on algae and BGA's?

I clearly have not had this plants for many years yet have no BGA, so are all my plants doing this as well?

Allelopathy is nice to talk about and all..............but the reality is I've never seen any evidence to suggest it occurs in aquatic plant tanks or the research on the field.

Grinding something up and putting it on cultures(of non target BGA or other organisms) in little wells is not a supportive argument to make this claim.
Maybe it happens, maybe I'll cure cancer, but I doubt both equally.

On a more basic level, you can add the plant and see, when you fail at controlling BGA, you can do a blackout and start adding KNO3 from now on so you do not get BGA in the future.

Regards,
Tom Barr

 

[daveedka]

Tom,
Thanks for the info. I had a little trouble beleiving the claim, but since I read it I thought I'd check it out. I read it at an online plant vendors website and that of course made me more suspect about the claim. As far as the 3 tanks, and the one with some BGA there are plenty of other variables that could contribute and affect things so I of course am working with many possibilities. ?The tank in question is the only one that I do dose any KNO3 in and that is very minimal. my nitrates stay around 10 ppm at all times, and anytime they drop below I push them back up with KNO3. How high can I safely go since NO3 seems to be the most popular answer? Also I have added some current (via submersed powerhead) but never felt that current was low before. Since the addition of more current, the BGA Growth seems to have accellerated.
The one thing I haven't done since changes is a blackout to reset things. I am currently using DIY cO2, but will be changing over to pressurized in a week or so. I had intended to blackout the tank at changeover time. Any info will be appreciated, at this pint I am going to assume that the blackout will take me back to square one, and from there the other adjustments I've already made should prevent future problems.
Dave