cyanobacteria...

How long does this stage usually take? And what is the best way to control it? Are there any dangerous side effects from it?

 

This will be a good resource for you:

http://netclub.athiel.com/cyano/cyanos2.htm

 

its a tough alge to get through theres chemicals but i dont think its the best way. i had it a couple of months and i found adding circulation, more frequent water changes, and adding a skimmer helped a lot to get rid of it.

 

Good link, I have just started to get some in my tank.

 

I tried some chemicals... I basically eliminated all of it within a couple of days... But after a couple of weeks I've seen small traces re-appearing... This stuff is tenacious!

 

That would be the problem with the Chemical method. If you haven't eliminated the cause it will always return.
Try the things Karlas wrote about and maybe reduce feeding and photo-period

J

 

Having just dealth with a flare up after changing my lights on a mature tank.....and 25 scarlet leg hermits. They will have you tank clean inside a week and keep it that way.

My $0.02
E