Cyanobacteria, BGA, Blue Green Algae = EVIL!

[kamikazi]

Cyanobacteria (Blue Green Algae, BGA)

This is green, slimy stuff that will cover just about anything (tank walls, plants, substrate, driftwood, rocks, etc). It comes off easily with touch or siphon and often will come off in sheets. It commonly has an unpleasant smell. It is very hard to get rid of and manual removal will only get rid of it for a few days.

Below is a list of possible treatment options or possibilities that I compiled from TPT posts. Many of these treatments are reported to have worked and others have reported they tried the same thing only for it not to work. The treatments that seem to be reported to work most often are a 5 day blackout and erythromycin. The only method I have seen that is reported to be 100% effective is a full treatment of Erythromycin.

Once you have killed it, it is important to try to determine the root cause and address that so it won’t come back. Common root causes: high light without CO2 to balance, low CO2, low flow, low nutrients/fertilizers for plants, abnormally high build up of organics.

Treatment possibilities for those nervous about using chemicals:
- Blackout: 5 days, 0 light getting into tank. Turn off CO2, feed fish as usual, use an air stone to supply oxygen to fish during blackout.
- Reduce Lighting: for example raise lights, reduce photo period, run less bulbs
- Increase flow: add a power head, second filter or upgrade filter to increase flow

Treatment possibilities that use chemicals:
- Excel: Double the recommended dose, for 4 days.
- H2O2: spot treatments, be sure to turn off filter for 30 mins during treament
- Erythromycin: Sold as Mardel Maracyn (don’t get Maracyn II) dose per package instructions for full 5 day period. There may be other sources but this is commonly found at fish stores and big box chain pet stores.

Below are links to two threads that discuss BGA and the primary sources of the information listed above.
HERE
AND HERE


My OP that began this thread:
How do I get rid of this stuff?

Standard 29 gallon
36 inch Coralife T5NO light
0 ammonia
0 nitrite
Nitrate in lowest category on test strip
Weekly 25% water changes
Planted tank
2 HOB filters (1 Top Fin 30, 1 Aqueon 30)

Been setup up and running for over a year, started having trouble with it about 3 months ago, right after I got the T5NO light. So I suspect that is problem, but I know many people use this light over 29 gallon tanks without issues.

It's growing on most of the plants, glass, and driftwood

[Optix]

pro-tip:

clean your plants
treat tank w/ maracyn (for 3-4 days)
BIG water change (>80%-90%)
up your nitrates to keep it from coming back

[wkndracer]

http://www.plantedtank.net/forums/ge...cs-advise.html

HTH you

[kamikazi]

Thanks for the link wkndracer

Every time I do a water change I clean as much as I can off.

I will try shortening my photo-period. See if that makes a difference. If not I will consider the maracyn.

[150EH]

I think you may be changing your water too often without CO2.

[kamikazi]

Originally Posted by 150EH

I think you may be changing your water too often without CO2.

So you think I should cut down to what every other week? twice a month? once a month? once every couple months?

I really don't know what the tank and plants can handle.
Can you explain how the water changes too often could be causing a problem?

[150EH]

Most articles claim a low tech tank should only do water changes every other month as fresh tap water has higher CO2 than the gassed out tank water so weekly WC's on these type of tanks gets the plants happy and pearling away for 24 to 36 hours and then 5 or 6 day with no CO2 creates a up and down cycle that can cause some problems and one is algae. There are some good articles that can help you keep your tank in tip top shape and this is a good one; http://www.barrreport.com/showthread...on-CO2-methods

[JackFu]

As long as your parameters are good, don't change the water in a low tech tank. Like 150EH says, it encourages algae. I wouldn't set a fixed schedule. Just watch your nitrates.

You didn't mention what substrate you are using. My low tech is soil and play sand. When I remove water cleaning my sand, I replace it with water from one of my gravel tanks, which only have java moss and a few stem plants. If I didn't have that option, I'd probably just return the siphoned water minus the debris.

[kamikazi]

Originally Posted by 150EH

Most articles claim a low tech tank should only do water changes every other month as fresh tap water has higher CO2 than the gassed out tank water so weekly WC's on these type of tanks gets the plants happy and pearling away for 24 to 36 hours and then 5 or 6 day with no CO2 creates a up and down cycle that can cause some problems and one is algae. There are some good articles that can help you keep your tank in tip top shape and this is a good one; http://www.barrreport.com/showthread...on-CO2-methods

Thanks for the info! Here is a question though, I have very soft water and over time the pH goes from neutral down to ?, the lowest I let it get was 6.3ish. If I go a every other month with water changes how do I avoid a big pH upswing or should I not be worried?

Originally Posted by JackFu

As long as your parameters are good, don't change the water in a low tech tank. Like 150EH says, it encourages algae. I wouldn't set a fixed schedule. Just watch your nitrates.

You didn't mention what substrate you are using. My low tech is soil and play sand. When I remove water cleaning my sand, I replace it with water from one of my gravel tanks, which only have java moss and a few stem plants. If I didn't have that option, I'd probably just return the siphoned water minus the debris.

Had no idea I shouldn't do water changes often in a low tech tank....

I have two tank, but are low tech but only the 29 is having the issues with the cyano.

The 29 is floramax with small pea gravel on top.
The other tank (40 breeder) is sand area at front, with organic choice potting mix capped with very small gravel at back of the tank.

One question unrelated to the topic, How do I clean the pool sand without sucking it all up?

[shrimpnmoss]

The reduction of WC might work on other algae, but I think one of the causes of cyano is lack of water movement and low O2 levels other words stagnate water. I had a vase biotope/walstad no filter experiment with no WC I got cyano within 2 weeks....stinky too...

[JackFu]

Originally Posted by kamikazi

One question unrelated to the topic, How do I clean the pool sand without sucking it all up?

I remove the larger part of my gravel siphon and just use the hose. Pinch it off and position it about a 1/4" off the sand. Release the pressure and the lighter debris will get sucked up. When you're done in that area, pinch it off and reposition it. You'll still get some sand, but not much if you're careful.

[prp427]

Ughh! BGA is the only thing that had me questioning whether or not to quit the hobby. I tried almost everything to get rid of it. The most disheartening part was doing a water change, meticulously sucking out all the smelly sliminess that you possibly can, and the next day its back and spreading before your eyes!!
Believe me, lower your lighting period and intensity (if possible) and it will slowly disappear.
Good luck!

[kamikazi]

Originally Posted by shrimpnmoss

The reduction of WC might work on other algae, but I think one of the causes of cyano is lack of water movement and low O2 levels other words stagnate water. I had a vase biotope/walstad no filter experiment with no WC I got cyano within 2 weeks....stinky too...

definitely not the cause for me...I have two HOB filters one on each end so there is lots of water movement.

[kamikazi]

Originally Posted by prp427

Ughh! BGA is the only thing that had me questioning whether or not to quit the hobby. I tried almost everything to get rid of it. The most disheartening part was doing a water change, meticulously sucking out all the smelly sliminess that you possibly can, and the next day its back and spreading before your eyes!!
Believe me, lower your lighting period and intensity (if possible) and it will slowly disappear.
Good luck!

thanks for the support and advice

[150EH]

My tap waters pH is 7.4, my tank pH is 7.2 in the morning and 6.4 by afternoon, so that's ok. Water movement like said above is very important, I just had a bad case of green water and bought 2 JBJ circ. pumps and a wave maker and my GW was clear in 2 day without any UV Sterilizer, so I was also from the school of low flow. But if you thinking "I do the same thing as these guys but I always have algae problems" then you have low flow too, my fish love the currents and my plants are so happy with more O2. I don't like the look of powerheads in my tank but you can always pull them out when it's time for a pic or hide em behind something.