Cyanobacteria - Blue-Green Algae (BGA)

[George Farmer]

Well my planted friends it seems my set-up has fallen foul to the dreaded Cyanobacteria (Blue-Green or Slime algae).

It is spreading very quickly over all my hairgrass and has started to smother the roots on my ivy. I have no idea of the cause, all water parameters check out fine - pH 6.5, KH 3, GH6, NO3 5 mg/l, PO4 0.1 mg/l. My husbandries haven't changed - 30% water change weekly (RO/tap mix) with added Dennerle ferts and KNO3.

My hairgrass and ivy are beyond saviour - I'm gutted to say the least.

My concern is finding the cause as obviously I want rid. I did experience a similar outbreak about 18 months ago. Then I sterilsed the whole substrate and did a complete strip down and clean.

Have any of you guys experienced similar problems?

 

[gaya]

I have it going on in a 10g. Well, i'm pretty sure it's slime algae. No matter what i do it comes back. It starts to cover my sand and glass within a week. I'm gonna tear this tank down once i rehome my fish.

 

[jimboliana]

Gutted mate,

Sorry to hear the bad news havent experienced it yet! If i see any info anywhere to help with the cause i'll let you know

 

[BigC]

Never experienced this personally, I usually get thread algae. According to the link below, you seem to have a build up of neutrients (dissolved organic material).
Could it be you are using too much plant fertilizer or overfeeding the fish. I'm searching through Diana Walstads book (Ecology of the Planted Aquarium) She too hints at a build up of neutrients.
http/netclub.athiel.com/cyano/cyanos2.htm

 

[RYO]

Bummer m8 tank was gettin to look good too. Not had that algae myself just poxy thread algae taking over my java moss, hope you sort it soon bud.

 

[nitro]

What a shame, all you hard work and effort and you get this Hope you can manage to avoid a complete strip down. Good luck!

 

[iggy01]

Sorry to hear that gf225 . I suffered with cyano last year and it drove me mad cleaning it off my plants every day. I initially tried to beat it by trying to follow the Redfield Ratio, but failed.

I then tried the 3 day blackout method. This worked for a week or two but it reappeared and seemed worse than ever.

In January after months of frustration I imported some Maracyn (erythromycin)from the U.S. and this killed it off. I haven't seen it since.

If my tanks were to be infected with cyanobacteria again I would do things differently. When I did my blackout last time I didn't add any KNO3 because my test kit said I had around 12.5 mg/l of nitrate, which I thought was ok. I have since discovered that test kits can tell lies and they're not always to be trusted.

If you wish to try the blackout method this is the procedure

Clean as much of the cyano out as possible. Do a 50% water change. Clean the filter. Add 1/4 teaspoon of KNO3 per 80 litres to the tank. Turn off the Co2. Blackout the tank....bin bags etc...no light to enter the tank whatsoever. Forget about the tank for 3 days (not easy I know). After 3 days uncover the tank. Do another 50% water change. Add another 1/4 tsp of KNO3 per 80 litres. Turn the lights back on. Connect the Co2 up again. Continue to add 1/8 to 1/4 tsp KNO3 twice a week. Hopefully you won't see the cyano again.

Many people cringe at the thought of the blackout method, but if my tanks became infected with cyano again.....which I hope they won't because I now add KNO3, I wouldn't hesitate to try it.

Good luck!

I've just re-read your post and noticed you are already adding KNO3. How much are you adding?

 

[drunkenmonkey]

I have that problem too...

This website: http/www.thekrib.com/Plants/Algae/cyanobacteria.html has some pretty good information. I'm not too sure if i want to try one of the cures because it can possible affect the friendly bacteria, causing the ammonia and nitrite levels to rise =S

that really sucks though... your tank is gorgeous

 

[Nospherith]

Maracyn! This is an antibiotic and will kill the cyanobacteria within days, sometimes with only one dose. I hope you didn't pull the grass. I just looked at the update on the journal and wow it was looking spectacular.

I know you folks in the UK don't have Maracyn there, but it costs only around $6US for 8 doses (for a 20g). You'd only need 2 doses to kill it. I wouldn't know how much more it is for import but with a tank like that it's worth it.

It's odd that out of all the kinds of algae there is that the blue-green would be the only one to cause you trouble, whereas it's the only algae I know I can thwart. Maracyn does the trick everytime.

Blue-Green algae is supposed to indicate low nitrates, so like Iggy said you could probably try hyper-dosing KNO3 (safe enough for fish of course). Maybe that might help. Good luck.

 

[jimbooo]

what a bummer, sorry to hear that GF225. i had a small outbreak in my riccia when i first submerged it in my 12G. i just picked it all out with tweezers, took ages but never reappeared. must have been lucky i suppose.

good luck with it

 

[Waterloo Kid]

A while back I tried to beat it with KNO3 dosing. When I tried that something went bang in the tank causing a pH crash and I lost loads of fish and my vallis practically dissolved. After 3 weeks it's on its way back to life at last. After the pH crash I stopped CO2 and KNO3 and reduced lighting to 5 hours a day (12 a day on weekends) and only 96W of light in my Rio 400. As all my plants are low light plants, they are doing fine (if growing very slowly), the blue green has vanished for the first time in 2 years and the fish are fine.
My advise would be to reduce lighting for a while to see if that helps. It's one of the easiest things to do and can really help (IME) Easily reversed too. My phosphates are through the roof again at over 1mg/l. Can't remember my nitrate reading off hand but I expect it to be less than 5mg/l.
Anyway, that's what sorted it out for me, at least so far.

WK

 

[George Farmer]

Thanks guys.

I dose 10 mg/l NO3 weekly - it is zero by the end of the week though so I'll try adding more.

Are antibiotics fish and plant safe?

 

[ryan]

I had the same problem. Apparently it normally comes in on plants etc or sneaks in some how. Mine was a nightmare and it took ages for me to get rid of it, I had to lose all the plants and cover the tank in a towel for around 2 weeks, nothing else seemed to work. Each thing I tried seemed to work but after a few days it would come back ever stronger only taking light away had a large effect.

 

[iggy01]

Thanks guys.

I dose 10 mg/l NO3 weekly - it is zero by the end of the week though so I'll try adding more.

Are antibiotics fish and plant safe?

If your nitrates are at zero by the end of the week then it's possible that's encouraging the cyanobacteria. I think it's a good idea to never let it drop below 5 mg/l.

Maracyn (if you're able to get hold of any), is safe for fish and plants. I used it myself to cure the cyanobacteria and it didn't effect my fish or filter bacteria. The dosage is 1 tablet per 10 gallons of water for 5 consecutive days. Some dose at half the measure because they say this is enough to kill the cyano. Others say if you dose half measures, you run the risk of not killing off the cyano and a stronger anti-biotic resistant form of cyano appearing.

Good luck!

 

[Jen]

George, Big Al's sells Maracyn, and I used it in an attempt to cure internal paracites. Didn't work for that, but it had no ill effects on my fish, plants or bacteria.

I don't know if Big Al's ships to the UK, but if you want to try it, I am going to that store tomorrow and would be more than happy to ship it out to you. I don't know how long or how much it would be to ship it to you, but if you wanted to use it, and can't get it over there, I can get it for you.