Old annoying topic - cyanobacteria

[Spink]

I know this is a "Been There Done That" topic, but I used the search function and can't find any answers, so I'm hoping someone can help.

I have cyno in my 60 litre lounge tank.

It currently houses sparkling gouramis, pygmy cories, celestial pearl danios, a few killi's and a male fighter. unfortunately, a few of the fish have been dying off lately, which I'm putting down to the excess cyno in the tank mucking up the water parameters.

I had fluffy algae in the tank but couldn't do the double dose of flourish thing as i had twisted val in there which I love. Now I have cyno all over everything and I want to get rid of it.

My plan was to black out the tank and do small water changes daily.

Questions:

- will the black out have any adverse effects on the fish?

- if I put the val in a small black container, cover it over and float it in the tank as well, will that kill off the cyno but not the val?

- will the other plants suffer from the black out?

If anyone can help I'd appreciate it because it's a favorite tank that I love and i just don't want it to get out of hand any more than it has.

[lmsmith]

Plants need light and darkness in order to 'eat' and grow. Same goes with algaes. The idea behind a black out is that the establised plants can get their nutrients from the substrate or their reserves, but the algaes and cyano will die out. That being said, I don't know why you think the val would do any better floating in a container vs being treated the same as the other plants. Is there something specific about val?

The fish will be ok, just make sure you ease them into it when you stop the blackout (take off the coverings, and leave the lights off until they get used to it) so you don't shock them. I don't think people feed the fish during a blackout, but I've never had to do it so I'm not an expert by any matter of means.

You may loose a couple of plants, but I think generally as long as they're well planted they'll be ok. How long are you planning on doing the blackout for?

[Spink]

The reason behind the val in the container was i was thinking about the double dose of flourish, but I think that will feed the cyno rather than getting rid of it. (double dosing flourish will dissolve the val plants completely)

I was planning on trying the black out for a week, and doing partial water changes daily, and still feeding small amounts of food, just to keep the fish on good condition.

If it hasn't worked in a week, i would keep going until it was gone, as long as there were no adverse reactions from the fish and the plants, but there are only a few crappy val plants, one java, a cardimine and a crypt left in the tank now.

[lmsmith]

I personally prefer the natural methods of getting rid of algae rather than adding bottles of expensive chemicals into my tank. I'd go for the blackout method for a week or so before using florish excell. I know there are heaps of other people out there who swear by it though, each to his own.

[Discusguru]

If it was me, I would just drop 1 Era tablet in and save all the time and effort.

ron

[alanmin4304]

Flourish excel will not control cyano as it is a bacteria rather than an algae. It usually arises because the phosphate/nitrate ratio is out of whack and you have too much phosphate. Furan 2 will kill it also and is usually easier to get hold of than erythromycin. If you don't get the water corrected it will come back. Water changes are the best and easiest way usually.

[phoenix44]

that and add some phoszorb to your filter - remember to fill the phoszorb jar with water and keep it covered for 10 minutes before you put it in your filter!

[alanmin4304]

If you use phoszorb you will strip the phosphate and put the ratio out of whack again--- real algae this time. Do water changes and antibiotics. I prefer furan as I killed the good bugs with E and lost a lot of fish with ammonia/nitrite once and have stayed away since. I have tried some other antibiotics I had but the didn't work.

[Warren]

I agree with Alanmin, waterchanges are the best answer. Cyno is caused by excess phosphate in the presence of no nitrate or excess nitrate. Phoszorb will reduce the phosphate level and do so quite quickly but not effect the nitrate level. Nitrate is also toxic to many fish (as low as 40ppm for some species). Many tanks have nitrate levels of 100ppm or higher. This will promote cyno as well as seriously reduce the lifespan of most fish. You could use phoszorb for a short time to pull the phosphate level back quickly but remove it after a day or two - but this is expensive and waterchanges will do the same thing. If you don't remove what's causing the cyno it will just come back so antibiotics are only a temporary fix and also wreck your filter bacteria.

Check the water you use for waterchanges is not rich in phosphate as well. There should be no measurable content. It's much harder to test for but make sure there is no dissolved organic content either or this will convert to nitrate with a day or two. I had a very big problem many years ago with 100+ ppm nitrate all the time. I could do a 90% waterchange and get it down to 20ppm. 3 days later it was back over 100ppm! I finally set up a brand new tank with nothing else but water in it and a Fluval filter. I ended up with the same result - high nitrate which went to low nitrate after a waterchange then back to high nitrate within days.

As long as your tap-water is good quality it will be fine. You should try doing 25% waterchanges every 2-3 days until the cyno goes away. Then, 50% waterchanges once a week will make sure it stays away and will make the fish much more healthy. Let the cyno grow like mad in the meantime and siphon it out during waterchanges - this will help burn out the phosphate and nitrate.

Also, try reading this - http://www.thekrib.com/Plants/Fertilize ... onlin.html

It's a great reference experiment that links cyno directly to phosphate and nitrate.

[caserole]

Warren hit your answer on the head spink.

There IS phosphate in our tap water!

[Spink]

why do I only have this problem in one tank though?

Will sunlight have any effect on the increased cyno?

[Caryl]

May make it worse. Cyano seems to take off when the tank gets out of balance. What has changed in that one tank I don't know but something has and it is to the cyano's liking

I got mine when I added some plants that had a little of it on them and it took off really fast. After trying the blackout and other natural methodes I finally used erythromycin and it got rid of it very quickly, and it hasn't returned since.

I have a bit of spare erythromycin if you want to try it. Unlike Alanmin4304, I did not notice any change in my filter bacteria and didn't lose any fish when using it.

[caserole]

Erythromycin isn't supposed to affect you filter bacteria.

[Caryl]

No it isn't but alanmin4304 said he had problems after using it and lost quite a few fish I think.

[skaffen]

you can still get a toxic spike when all the Cyano dies off at once. Happened to me on the third day after using Ethrowhatsamcallit, lost some fishies . Did get rid of the Cyano though

It was the bigger fish that perished, lower gill to body mass ratio?

[Caryl]

It is important to siphon the dead stuff out often as soon as it starts dying off (which is within hours)

[alanmin4304]

Caryl is on to it. Dead bugs and dead leaves contribute to raising the nutrient leval so siphon them off and remove dead leaves fom large plants like amazon swords.

[Spink]

So if I get hold of some erythromycin and use that, I'd be better to do it when i'll be home for a few days so i can keep an eye on the tank and siphon out the gunk?

Where do you go to get it? (maybe I'll have to take Caryl up on her offer and write her an article for the AqW mag!)

[Caryl]

You must keep an eye on it as it dies fast so you need to keep cleaning it out at least once a day for 3 or 4 days (depending on how bad it is). Erythromycin is a prescription only antibiotic and you get it from a Dr (if he will give you some). I know a couple of doctors who are able to give me a few tablets when required. In fact I have a pill bottle here with this written on the label:

Mr Guppy

Take one tablet with food once daily until tank clears :lol:

Another bottle has;

Add to tank until fish float to the surface then stop :roll: :lol:

Am happy to send you some if you want spink

[skaffen]

I was careful to remove as much as possible, but I still got an overnight spike. I suspect I had a lot of cyano in my substrate...

[alanmin4304]

The ammonis spike can be caused by the antibiotic killing or reducing the effectiveness of the nitrifying bacteria.

[Dixon1990]

I have got my main, nice tank covered in it, it grows so fast, im going to use the magnet cleaner, to get as much of as i can, and syphon it out, then do a black out, then il use a some antibiotics if neccessary.

ITS SO ANNOYING!

[alanmin4304]

Get the balance in the water right is the important thing.

[Dixon1990]

So what do i need to test for, and fix?

I really want this tank looking good.

It has 4 4foot t8 bulbs on it, has aquatic mix under the sand, and co2 running, might stop the co2 though, the fish arent liking it.

[alanmin4304]

It is all about balance. Your plants will not use a lot of nutrient including CO2 until they get established. Strong light and fertilizers in a well established heavily planted tank is good. You need to start slowly with plants just like with fish. Until the plants get established you are just feeding the algae.