its called black hair brush algae...how ever it is actually part of the red algae family. Usually comes hitch hiking on the backs of new plants introduced or it will come in the stomach of a new fish. I have some as well. I am keeping it at bay as much as i can and i will share what i know. First off...as far as fish are concerned, the only one that really eats the stuff effectively enough to do anything about it are siamese algae eaters. Now before you go and buy some of those...arm yourself with some info on them....as they are not flying foxes as some stores would have you believe...and they are not false siamese algae eaters...infact they are rare imports..and the other two i just mentioned will not eat algae...there is a link i have with identification for you...ill get it in the morning as im about to go to bed....dont be fooled..most stores think they have the proper fish..and they dont...i proved four stores in my area wrong to this effect.
The second thing you can do, which i see as being very popular is tear the tank about and use the bleach method. I know this sounds extreme..but thats how serious this algae is. They recommend a 1/20 bleach to water mixture, and dip the plants and decorations in one by one for about 5 minutes each. Then wash with clean water and re-install. You have to be very cafeful with this method..as most fine leafed plants will definately suffer damage.
Another method is the use of copper...but for this..you can have nothing that is living in the tank...it will kill fish, inverts..etc...and most likely kill fine leaved plants.
Some ppl may suggest algaecides....i did an experiment with algae destroyer brand..its suppose to be one of the most harsh..and it did kill it...only to have it come back in a week alot worse.
Thats about what i know of it....good luck to you..if the tank is small i would use the bleach method personally...im about to do it myself...this stuff is unbelieveable..i have never seen any algae like it all these years...if you research it..you will find the same info that basically i just gave you. Do the usual and check your parameters..but this is one of the rare forms that appears hitch hiked on other plants and animals..usually imports from asia. As in the case of my tank where everything was in check. As for it just sprouting up...it takes a couple of weeks..it looks dormant at firsth..then within a week or two..it will take over the tank..so dont be surprised to wake up to lots of it in a couple weeks if left untreated...and just removing the leaves will release spores into the water...hope this helps...it sucks i know..im losing my mind over this stuff...150 gallons is hard to treat
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