I have a 250L tank with medium plant and 2 42" tube on top. 1000l/h filter, DIY CO2 system with fish. Recently green slimy algae started appearing on the front side of the aquarium. where i think its more exposed to light. I have been using algae control solution that i brought from the pet shop. I am putting about 5ml every three days for last week. the green algae seem to be growing more and not stopping. Its getting more and more every day, like growing in patches and the patches and growing bigger and greener. the solution seen to do little good and i think that the algae is taking over. Please anyone out there can help me. I have check the ammonia and nitrite levels and that is normal, no reading everything is 0.

anyone out there please give me some suggestions.

Sounds like cyanobacteria which isn't actually an algae so algae stuff won't get rid of it. I don't know how CO2 affects it. Usually I suggest blacking out tank for a few days but not sure if you can do that with CO2 running.

As a final resort you can use Erythromycin to get rid of it but it is a prescription only medicine and doesn't help if you don't know the cause so it may return.

get a uv filter

Stop the CO2 - excess levels cause exactly the problem you have.

UV filter only helps for algae thats free floating and actually goes through the filter to get zapped.

Got any algae eating fish in the tank? A bristlenose pleco (the small sort) might fix your problem.

Cheers

Ian

IME bristlenose wont touch it if its cyano. i have heaps of algae eaters and none of them touch it.

what caryl said. you really need to find the cause, i think its too much phosphate, along with either no nitrate or high nitrate. pleas correct me if im wrong.

I got rid of my cyno using the black out method.

True.. if it's cynobacteria then the pleco wont be so interested.

But if you are setting your tank up to grow plants, well algae is a plant, some will grow no matter how well the tank is managed. A couple of little fish with built-in glass scrapers can just make life so much easier.

Cheers

Ian

I've seen a couple of cyano blooms set off by very low nitrate and slightly high phosphate. If you can do lots of changes with water that has no phosphate (eg rain water, or deionised water) you can bring cyano under control.

It's not quick though, will take weeks at least. If you do this, maintaining your nitrate levels at 5-10ppm can help speed things up.

Blackout took less than a week for me.

what does blackout mean? Just turn the aquarium tubes off for a while (week or so), or cover the whole aqaurium with something (like dark cloth) so no light gets in.please reply soon coz its trying to take over my aquarium. thanks for other hints.

blackout means cover with a blanket or similar so no light gets in. erythromycin will get rid of it in 2 or 3 days max, then you need to find the cause. good luck

some will grow no matter how well the tank is managed

Oh I'm glad you posted that...I thought anything kept under water would have some kind of algae on it, at least that's what I've been telling myself about the ornaments in the tank (have been there for awhile)...so my thinking was right then!

Caper

So how and where do i get this stuff, erythromycin. I have called one vet, cut long story short..he said that I have to get him some of my fish and water for him to do all the research and that will take time for him to come up with how he is going to use erythromycin.

I have some spare if someone nearby doesn't offer any.

You are my god... How can I get some from you? I am willing to pay, if required. Where you live? I am in henderson.

If your nitrates are 0 you might want to consider a bit of nitrate fertilizer. It might help keep it away (or add more fish? Someone here could tell you if your tank can handle more)