black algae, bad?

[fkabbage]

i have a 40gal. with three African cichlids, a syno. catfish, two upside down cats, and a 4-lined cat and my tank has aquired dark blue/blackish algae on my rock. since the algae two sailfin plecos have died and they were on the black algae. is it bad and can it be the reason for my loses.

thank you

 

[Lupin]

Dark blue? Sounds like blue green algae or cyanobacteria to me. I believe this one is toxic to fish when consumed. Could you please indicate your water parameters? Remove the algae manually.

 

[fkabbage]

thanks for the help. i dont know the parameters but will inform uyou when i find out please keep checking to see when i do.

 

[fkabbage]

how did i obtain this algae.thanks for your help.

 

[PostalPenguin]

If it is blue green algae/cyanobacteria then it came come from low flow, low nitrates or dirty biofilters.

Try increasing the flow or you can take hydrogen peroxide and squirt it directly onto the algae with a syringe.