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cbster
07-14-2004, 6:35 PM
Well now I have a case of cyanobacteria I tried the three day blackout twice with it coming back both times. so I am treating with Maracyn (half dose) and I am into the fifth day today it looks like it is killing it but not as much as I wished for the fifth day. but the cory cats are eating or just knocking it off of everything like crazy which I haven't heard of in my research of this stuff. so my question is after today should I do another three day blackout to make sure this stuff doesn't come back or should I just see what happens?



P.S. Plantbrain and Djlen I have been doing everything you told me from getting 4 SAE's and the fert regime which the plants are starting to grow alot better than they were after the outbreak of BBA

plantbrain
07-14-2004, 7:54 PM
Clean the tank good, the filter etc, increase the current perhaps to areas effected, remove fine needled plants for a little while, keep after the alga and repeat. You are not doing something right here. It should not come back if you have been adding the KNO3, keeping the CO2 up etc.
Cory cats most certainly will prevent it from growing anywhere they dig around. So will current.

It'll come back after the antibiotics also, might take maybe 2 weeks or so. I tell folks the blackout is faster than antibiotics.
But you need to figure out what you are doing outside our advice that is not helping the plants to grow well and also to perhaps add a bit more KNO3.
Harassing algae for a few weeks when a tank has been infested will often be needed. Just keep after it and fluff the stuff off and net it out, do 2 water changes a week and remove it etc.

When plants look pretty good, try another blackout.

Regards,
Tom Barr

djlen
07-15-2004, 5:00 PM
If the plants are growing and you keep dividing them to gain more plant mass it will eventually start to recede.
As Tom says, cleaning it up and getting the plants growing well will do the job. Keep after it. Fluffing the plants to loosen it up, immediately followed by a water change will help a lot.
Bottom line......keep the stuff as minimized as possible and keep the ferts up to grow the plants.
What are your latest test results for N & P content and what are your CO2ppm? Are you dosing traces?
This has happened to virtually all of us at one time or another. You're not alone here.
Keep after it.

Len

EhfiYann
07-15-2004, 5:53 PM
The old-fashioned approach to reducing algae, shutting off the lights for a few days, seems to be not so effective in dealing with some cases of cyanobacteria infestation. More, I'm not certain if *algea-eating fishs* will actually eat cyanobacteria if they have access to another food source.

Cyanobacteria is generally blue-green in color. It is not really an algae, but a bacteria containing chlorophyl pigments. It is primarily a photosynthetic (alga properties) organism, but does have the ability to grow in low-light to no-light areas because of it’s unique bacterium like qualities. Some species are capable of nitrogen fixation. Their cellular structure closely resembles that of bacteria and on the whole can be treated like true bacteria. Nitrogen-fixing cyanobacteria need only nitrogen and carbon dioxide to live. They are often seen in anoxic environments. If you have a Phosphorus deficiency in your tank (or a N:P imbalance) and your plants are not growing, I would believe that the total available Nitrogen could be high. If that is the case, add trace amount of Phosphorus, change your bulbs to promote plant growth and competition.

Because cyanobacteria are gram-negative microorganisms, the best success I had in dealing with cyanobacteria outbreaks was using anti-biotics. Erythromycin (EM) is an antibiotic obtained from a strain of the actinomycete Streptomyces erythreus, it's effective against many gram-positive bacteria and some gram-negative bacteria.

It is sold as EM Tabs. Maracyn (not Maracyn II) also contains EM. Posology is 250mg per 10 gallons of water. Change 1/3 of the water in 24 hours. Repeat if necessary (most of the time one treatment will work).

EM, altough *gentler than other antibiotics* can severly disturb the ever-going, super important Nitrogen Cycle in your tank and have a very negative impact on biological filtration. Be carefull ! I suggest you monitor you Ammonia levels closely while treating. Oxygenation could prevent a disaster but will drive out the CO2 from your tank. You should stop oxygenating when the outbreak is controlled. Try to keep the water flow somewhat strong as it will prevent *dead spots* in your tank. It helps.

Good luck :cool:

plantbrain
07-16-2004, 3:56 AM
No, black out is 100% effective at killing it.

There are 2 basic genera that are found in planted aquariums and neither is N2 fixer.
Oscillitoria is the main genus and the O. splendens is the most prevelant species. This genus does not possess heterocyst and there is plenty of N present in any aquarium for BGA to grow anyway. No heterocyst, no N2 fixing in this genus.

Even if your cheesy kits test 0.0ppm, even if your Lamott test kits test 0.0ppm of NO3. They still have plenty as the resolution is nowhere close enough to measure N limitation in this genus.

I've looked at samples from dozens of folks with different tap water and tank conditions, many tanks over the years. Folks send and trade plants often and I've traded about 4-5 times a year for several years. I have a very nice microscope at the lab. It'll come in on plants, gravel grains etc, the spores will settle out from the air and start growing in about 20-30 days even if you had a sterile tank. Even if you kill it, it'll come back with the right conditions.

I can argue the same issue for antibiotics and BGA reappearing as easily as the blackout method.
Both methods are very effective at killing it.
I suggest a way of having it not reappear and also why and the method is 100% free. Did I say it was free?

N stressed plants and low nutrient environment will favor smaller organisms, not the larger higher plants. Generally unclean filters, poor circulation, low N, high DON will favor growth.

It's very easy to get rid of using a blackout for 3 days every time. It'll come back if you do not correct the cause, poor plant growth.

Either I've been fabulously lucky for many years and so have many others, or there might be something to it.

I've used antibiotics a few times and it took about the same time as a blackout, but a blackout is FREE and adding KNO3, cleaning the tank and increasing current heps to prevent it from coming back.

I'm not sure what part of Free make the method ineffective vs antibiotics which are not widely available over the counter or mail order in many countries FYI.

There is no fish or snail that will eat it. They are toxic. Cory cats can increase current etc along the bottom and cause it from form blankets on the substrate but they do not eat this alga/cyanobacteria.

The name classification is sticky one, they far different than any group of bacteria and much more advanced, but they are also different than eukaryotic algae. I would place them in their own group and most of the work in the past was/is done by phycologist, of which I am one. BGA is fine also, it's just a common name, if folks want to get more precise about names, then they should be specific and refer to it by the genus.


The other genus that is seldom found: Phormidium

Every sample I have ever seem has had Oscillitoria in it, even if it was not visible in the tank, under a microscope you can find strands of it all over.

It's still there, it's just not growing or taking over just like most algae.

The key is killing/removing the algae that's there, stopping it's growth and correcting plant growth issues, KNO3 it a plant nutrtient, antiboitics are not.

Addressing the cause is much better than simply killing an alga.
You need to do both, not just kill what's there. Otherwise no method really works and we chase our tails.

Managing algae is not difficult, grow the dang plants well and you don't have issues with it. It really is that simple.

Regards,
Tom Barr

daveedka
07-17-2004, 6:34 PM
Although the knowledge of the above posters is far beyond mine, I can say this. my 115 has BGA issues, and is currently in a stage where I intend to do nothing drastic. I clean as much as I can each week with my water change, and do a blackout if it gets bad. post blackout I get at least 2 weeks of the most beautifull algea free tank you will ever see. This tank is moderately planted and lit, and very new. As the plants grow, I am seeing less and less algea ( all types not just BGA) each week. I am confident that in short time The tank will stabilize and algea won't be an issue. And all I do is the "free" blackout that Tom has mentioned. It is highly effective for killing many types of algea until the right nutrient balance is found, and the plants choke it out for good. I used blackouts for years in FO tanks, and quite honestly, I don't get concerned at all with algea, just black it out and then work on whatever issue is causing it or allowing it to return. Just remember the blackout is the band-aid, you still have something to adjust but as was said somewhere earlier, it may just be that the plant mass isn't high enough yet. Blackouts are an easy and relatively cheap :D way to control things while you are learning.